This post is the current culmination of everything I have learned from my previous posts and polls regarding vampirism. All of those previous threads will now be ignored by me.
I am among those who believe that vampires and werewolves were last minute additions to this game. I believe this because of the unfinished way they were implemented and the way they break with the lore, not only of the way vampires worked in previous TES titles but against the very lore demonstrated in THIS game. I will explain my reasoning on this matter in the latter half of my post. For now, I would like to discuss potential improvements and the various ways they might be implemented.
1. The timing of the Stages is completely off. If a player chooses to remain in the least monstrous and least obvious stage, Stage 1, they are forced to feed 12 times a day since Stage 1 only lasts a half an hour of a 6 hour game day. This "feeding schedule" is completely unrealistic and can only be accomplished by actively questing in areas with large numbers of NPCs that vampires can actually feed on. If you are grouped for a dungeon or other group activity such as PvP it can be nearly impossible to feed as your entire group has to wait for you to sneak up on a suitable NPC and not aggro it so you can feed on them before engaging the NPCs in combat. Only Nightblades can currently feed while in combat as they can go invisible in order to sneak up on an NPC that has already been aggroed. As the pros and cons of each stage can have a definite impact on gameplay it is important that players have some control over the Stage their vampire is in at all times. This becomes even more true with the implementation of the justice system where Paul Sage assures us that other NPCs "will notice" vampires in Stage 4 and will not like it, suggesting that they will aggro on Stage 4 vampires in cities and towns. There have been several suggestions to improve this situation.
A. Change the Stage timer to 6 hours for each of the initial 3 stages in order to more accurately reflect how the stage timing worked in the previous TES titles where your vampire only had to feed ONCE PER DAY in order to maintain Stage 1 . Each day that went by without feeding also lasted an entire day/night cycle. So it actually took 3 whole days before your vampire was "starving" and city guards would attack them on sight. This is probably the most realistic and lore-friendly solution. Those who prefer to maintain their vampires IN Stage 4 will still be able to do so in the same manner they always have, by not feeding at all.
B. Lengthen the Stage 1, 2 and 3 timers to 2 hours each. This way it still takes at least 1 full game day to become a "starving" vampire at Stage 4 and gives players a more reasonable time frame to maintain the Stage of their choice than the current system does.
Several other suggestions have been made as to preferred lengths of time for each of the first 3 stages, with the very least "acceptable" amount of time for Stage 1 being a full hour. The main thrust of all of these suggestions is that, as it currently stands, Stage 1 is far too short. In that amount of time you can barely find an NPC to feed on and then enter a town and get to the merchants before you are in Stage 2 already. If you are in a city and busy crafting with your vampires even if you start at Stage 1 you can end up in Stage 3 and even 4 before you even know what happened. Roleplaying inside a city....HOURS can and do go by without a good opportunity to break away and leave town to go feed. Again, this does not prevent access to the latter Stages but merely gives players better control over what Stage their vampire is in. ANY system that enables this will be welcome.
**UPDATE TO ADD MORE INFO 11/20/14**
The actual Stage Timers (and their supposed effects, there is some argument as to whether or not they really work this way), for those who do not know, are as follows:
Stage 1 Vampirisim 30 minutes -You take 50% more damage from fire attacks. -Feeding reduces you vampirisim stage, sneak up behind an enemy humanoid to feed on them.
Stage 2 Vampirisim 60 minutes -Your health regenerates 25% slower. -You take 50% more damage from fire attacks. -Your Vampirisim abilities cost 20% less health to cast. -Feeding reduces you vampirisim stage, sneak up behind an enemy humanoid to feed on them.
Stage 3 Vampirisim 90 minutes -Your health regenerates 50% slower. -You take 50% more damage from fire attacks. -Your Vampirisim abilities cost 40% less health to cast. -Feeding reduces you vampirisim stage, sneak up behind an enemy humanoid to feed on them.
Stage 4 Vampirisim no timer -Your health regenerates 75% slower. -You take 50% more damage from fire attacks. -Your Vampirisim abilities cost 60% less health to cast. -Feeding reduces you vampirisim stage, sneak up behind an enemy humanoid to feed on them.
Source:
reddit.com/r/elderscrollsonline/comments/1zm3eo/life_in_eso_as_a_vampire_feedinghunger_mechanics/http://
If anything, the time for Stage 3 should be reversed with the time for Stage 1. It just makes more sense that a vampire that has just fed will look and feel more "normal" and that as the time between feedings lengthens they will degenerate more quickly. This might actually be the very easiest thing for ZOS to do.
EDIT 12/31/14 TO ADD: This would also please PvPers who have already expressed concern about how long it will take for their vampires to return to Stage 4 before returning to Cyrodiil.
2. Please give us some way to hide vampirism completely and return our vampires to the appearance they had BEFORE becoming a vampire. This is consistent with the lore of ESO for several reasons I will detail below. Here I will simply detail various lore-friendly suggested methods for its implementation. However, it is important to note that this should not be a "freebie." It either needs to be the result of a quest reward, an additional Skill that one has to put points into or in some other manner expend effort to acquire. It is also important to note that no matter how this is implemented, it needs to "break" at Stage 4. In other words, while using it, the Stages actually continue to progress as usual. At Stage 4 either the effect vanishes, revealing the Stage 4 appearance (the preferred outcome) or, even if the VISUAL effect does not disappear, NPCs can STILL tell there is something terribly wrong with your vampire and will react accordingly once the justice system for this is in place. No one wants this to be an "I don't have to deal with Stages" item! Nor is it meant to confer a permanent Stage 1. Those who do not want these options can simply skip the quest if there is one. Just please don't make it tie to an Achievement.
A. A costume/disguise that you can acquire from either an NPC quest giver (and that you must complete the quest for in order to be able to keep) or that you can purchase (for a fairly large amount of gold, meaning you'll still have to "work" in order to be able to acquire it) from an NPC vampire merchant. This is probably the LEAST appealing suggestion as it would preclude using any other costume or disguise while using it.
B. A slottable item (like, for example, Finvir's Trinket) that you can acquire from either an NPC quest giver (and that you must complete the quest for in order to be able to keep) or that you can purchase (for a fairly large amount of gold, meaning you'll still have to "work" in order to be able to acquire it) from an NPC vampire merchant.
C. A potion that lasts a minimum of 2 hours and a maximum of 6 hours that you can acquire from either an NPC quest giver (and that you must complete the quest for in order to be able to keep) or that you can purchase (for a fairly large amount of gold, meaning you'll still have to "work" in order to be able to acquire it) from an NPC vampire merchant. In the case of being able to acquire the potion from an NPC quest giver, once the quest is completed you would then be able to return to that NPC at any time to acquire more of the potion.
D. A potion that lasts a minimum of 2 hours and a maximum of 6 hours that you can acquire via the Alchemy Skill.
E. A new vampire Active Skill.
F. A new vampire Passive Skill.
Ideally, in the case of new vampire Skills, you would still need to complete a quest to unlock access to these skills. Either could be implemented as part of the upcoming Spellcrafting system.
3. Bring back the ability to "charm" an NPC and feed off them WITHOUT aggroing them, as it is in Skyrim/Dawnguard. Since feeding does no damage this is reasonable and in accordance with previous TES lore. Once the justice system is in and guards will aggro and bounties will be incurred and characters CAN attack townie NPCs it stands to reason that vampires will be able to feed on them as well. Those who DO NOT WANT TO KILL THEIR PREY, and thus incur a bounty or be attacked by guards, need an option to feed that does not aggro. It would be fine for this to only be available to neutral NPCs and not hostile ones.
4. Change the feeding animation. Frankly, it's terrible. When feeding from stealth, the vampire should jump on the back of the NPC and bite the neck. Keep the current screaming, that's great.

When feeding from a charmed victim the vampire should approach the NPC from the front and then either bite the neck or the victim can offer their wrist that the vampire then grabs and feeds from. If a sound effect to go with the animation is necessary a soft gasp from the victim would be fine. Bonus if the victim gives a bit of a drunken stagger afterwards.

5. While no one wants to change the looks of Stages 2, 3 and 4 there is some controversy over the look of Stage 1. The incredibly bright white skin and glowing red eyes still make vampires look far too "obvious" when compared to previous Stage 1 player vampires in the stand alone TES games and also goes against the lore established by ESO. Some people also don't like it that they lose the look of the facial makeup they selected at character creation. Many simply want a vampire that looks SUBTLY different from mortals but can generally "pass" as mortal at first glance. Some would actually like to change the appearance of Stage 1 (and therefore do away with the current look of Stage 1) while others feel a new Stage should be added and that this new, more subtle, look should become Stage 1, the current Stage 1 should become Stage 2 and so on down the line resulting in 5 Stages instead of the current 4. The easiest way to achieve this new look might simply be to implement it as an additional look to the "disguise" detailed above so that there are TWO different choices (and ideally, we would have access to BOTH). However this might be implemented, there are basically 4 potential sets of ways for it to look.
A. Skin paleness is dialed back so it doesn't glow the way it does now. Skin is STILL paler than "normal." Ditto for khajiit fur. Makeup is returned to the way it looked at character creation. Ditto tattoos. Eyes remain red.
B. Skin paleness is dialed back so it doesn't glow the way it does now. Skin is STILL paler than "normal." Ditto for khajiit fur. Makeup is returned to the way it looked at character creation. Ditto tattoos. Eyes return to original color selected at character creation but still glow SLIGHTLY.
C. Look is completely mortal EXCEPT that eyes glow red as they currently do in Stage
D. Current Stage 1 skin paleness is left as is but makeup, eye color and tattoos are returned to normal. (For purely aesthetic reasons this one is my personal favorite.)
6. Some people do not care for the way that the vampirism that was designed for ESO lets vampires walk in the sun without penalty. And it is pretty lore breaking when compared to the other ES games and since I am addressing vampirism from the "lore" as presented in the previous games as well I'll mention this also. While it may be "too late" to change it now there are some ways in which a more consistent with previous games mechanic could be implemented. Vampires COULD take damage in sunlight though this should be slow and it should be some times before the vampire collapses and dies. If possible, they should take only half of the regular damage if they remain in shadow but, again, I'm not at all sure that is something that could be done. However, they should take NO damage when indoors or in a dungeon or other underground location. Further, a potion could be made available that gives vampires sunlight immunity for an hour, just like a food buff. This would at least mean vampires don't get to walk about in the sun without consequence and would make them a little more challenging to play. While this would mean "retconning" the ESO lore and I am therefore neutral to slightly opposed to the idea, there are those who feel that since it would be a better mechanic than the one selected and more consistent with previous TES lore, it should be done. I include it here in the interests of completion of the various ideas people have come up with to improve the player experience of vampires.
7. Vampire only emotes. This is just fluff but is the sort of fun thing that adds to immersion.
/lungehiss The vampire lunges forward and hisses.
/mist The vampire becomes a column of mist. Animation can be maintained while WALKING only.
/barefangs Vampire snarls, baring their fangs, which are visible in the animation.
And now, the reasons why...
It is apparent that vampires are MEANT to be able to pass as normal humans in ESO and that the vast majority of them do so. I have 2 reasons for believing this. The first, is Count Ravenwatch.
This is Verandis Ravenwatch when you first meet him. Note that he looks completely mortal.

And this is Verandis Ravenwatch AFTER you find out that he is a vampire and has been one all along.

He TELLS you that he "hides" his condition at the insistence of his good friend High King Emeric. Now, there are those who say that this is because he was turned into a vampire directly by Molag Bal and therefore INNATELY has the ability to do this whereas player vampires, having contracted their vampirism via bloodfiends, do not. In other words, player vampires are a lesser order of vampire and therefore will never have this ability. Now, there are 2 reasons to disagree with this assumption. Because that's exactly what it is, an assumption. Verandis never says he was made a vampire by Molag Bal. He never says how he was made a vampire at all. He DOES refer to Molag Bal as his "master." That may suggest that MB DID turn him BUT it is also easily read as the designation ANYONE who serves Molag Bal would give the Prince of Schemes and may very well NOT indicate that it means MB is his "Maker." IF Molag Bal had turned him directly that would indicate that Ravenwatch is a "Son of Coldharbor" BUT there are no "Sons" of Coldharbor in ES lore, only "Daughters of Coldharbor." Even though Lord Harkon in Dawnguard claims to have been made a vampire directly by Molag Bal in Dawnguard his story is in direct contradiction to all previous lore on the subject. So while it is POSSIBLE Verandis was made a vampire directly by Molag Bal it is unlikely, nor is it ever stated outright.
We, as players, do not KNOW how Ravenwatch became a vampire or of what bloodline he may be. What we DO know is that he is a very powerful sorcerer and he demonstrates this throughout your association with him during the questline he appears in. So when he says he "hides" his condition at the insistence of King Emeric it is not at all unbelievable that what he means is that he uses some form of sorcery to do so and that it is NOT, in fact, an innate ability conferred by his particular form of vampirism. Plus, the very fact that he says he "hides" it indicates that it is NOT a normal and innate part of his particular form of vampirism to be able to look mortal but rather is something that must be effected by other means. In other words, he wouldn't have to "hide" it if his normal state was to look mortal.
Indeed, AS a vampire, his appearance is exactly like that of a Stage 2 player vampire, further indicating that he IS, in fact, a vampire of the Noxiphilic Sanguivoria variety, the type of vampirism that player characters contract. Long story short; If Verandis can do it there is nothing keeping ZoS from implementing a lore-friendly way for player characters to do it.
My second example in support of my contention is Lamae Bal herself. Throughout the vampire quest she looks completely mortal. Again, naysayers will say that she IS a Daughter of Coldharbor (and she IS, no argument there) and that therefore she will be possessed of powers and abilities that will not be available to player vampires. They may even further contend that since one starts their transformation into a vampire via an attack by bloodfiends they are not "really" even children of her line and are therefore of an "inferior" strain that gets hungry super fast and looks obviously monstrous much of the time. But I call shenanigans on this argument. Rahaja, the initial questgiver in the tomb refers to "the history of our kin" with the "our" including you, the player vampire.
At the beginning of the quest Lamae Bal herself says the following, "Children, this is your kin. Life still flows within its blood. Tear it out, drain it, so that it may join us."
When the vampires there are finished drinking your blood she says, "Now you are one of us."
There is every indication that you ARE one of her "children" and in no way different than if she had in fact started the process herself. She certainly never says otherwise and there is no reason to believe otherwise.
**UPDATING TO ADD NEW INFORMATION 11/20/14**
I re-ran the vampire quest today and they have changed Lamae's appearance to that of a Stage 2 vampire. HOWEVER, HER ENDING QUEST DIALOGUE REMAINS THE SAME, CLEARLY INDICATING THAT VAMPIRES HAVE THE ABILITY TO HIDE AMONG MORTALS.
But the final kicker is at the end of the quest. When you speak to her again she says, "Your kin live among the mortals. They may be wearing rags or crowns. They may hide within or rise above the masses. Find them. They await." You can see the video where she says this here:
https://www.youtube.com/watch?v=KRQepUQ0OTU at 1:40.
If THAT does not indicate that vampires SHOULD and were INTENDED to be able to pass as mortals, I don't know what does. Because, obviously, vampires DO live unnoticed among mortals and the ONLY way they can do this is if they do NOT look like insane monsters more akin to zombies than vampires and as if they are about to eat the face off everyone they encounter.
**UPDATING TO ADD ANOTHER EXAMPLE 11/20/14**
What may be the most clear cut example of the fact that vampires are SUPPOSED to be able to look COMPLETELY MORTAL is the case of Heloise Menoit, a healer you meet in Rivenspire in the 20's level range. She has been scratched or bitten BY BLOODFIENDS. Over the course of the questline she is preoccupied with "hunger" and gives several indicators that she is becoming either a vampire or a bloodfiend herself. Ultimately she attacks and kills members of a family you and she are trying to help. She has clearly already become a vampire when you find her with the dead bodies BUT SHE STILL LOOKS COMPLETELY MORTAL. Only AFTER, you the player, are SUPPOSED to discover that she is a vampire does she LOOK like one. Up to that point, even AFTER she has clearly transformed into a vampire and started killing, she still looks utterly mortal.
For confirmation see video of the quest in question here:
https://youtube.com/watch?v=5SMkrjoi_PE#t=311
Now, obviously, this is a plot device and, frankly, a really poor one. It's being done so that when various vampires are "revealed" it's a surprise. But the problem here is that, again and again, we are shown that vampires CAN AND DO HIDE among mortals...and they do it by LOOKING MORTAL. Clearly, Stage 1 really should have a completely mortal appearance as, as Heloise PROVES, even lowly vampires like those turned by bloodfiends and NOT just special snowflakes like Verandis, can do this (look mortal) as a NATURAL part of their condition. It is therefore LORE that they can. To keep this ability from players is not only just petty but it's utterly illogical.
Now, as far as mechanics go, you DO pass as mortal among the NPCs in the game. NONE of them, including other vampires for that matter, KNOW that you are a vampire. Every single one of them is completely oblivious to this fact despite the fact that your appearance, most of the time, is the stuff of nightmares. Now my understanding is that the justice system IS going to change this, for Stage 4 vampires. My HOPE is that, at Stage 3, NPCs will also start making the usual cracks about not liking the hunger in your eyes we got from Skyrim. But since it seems that in Stages 1 and 2 they will still be clueless, it stands to reason that those appearances should at least be passably mortal. And one way or another, vampires SHOULD be able to pass for mortal and the appearance should match up with what we experience with the mechanics associated with each Stage.
Lastly, there seems to be a belief that it is somehow "important" that vampires be easily visible in PvP and that therefore the blindingly white skin is a must. However, several different armor types already allow a vampire to completely cover their appearance. Since this is true in PvP there's really no reason why other methods, such as the above mentioned "disguise," cannot be used as well. There also already exist ways to circumvent the ability to "hide" vampirism in PvP such as a particularly popular and questionable add-on that identifies not just vampires but werewolves as well. In addition there will soon be an actual SKILL that will let you see who the vampires are. With this in mind, the truth is that there's no actual way TO hide vampirism in PvP so there's no reason to disallow an appearance disguise if the player wishes to use one. It has no effect on PvP one way or the other. So let's put the, "You have to be ugly because PvP reasons" argument to rest here as well. It holds no water.
Powers that be at ZoS, I hope you will examine this proposal and realize that implementing it will result in better, more lore-friendly, and certainly more enjoyable vampires. Doing so will take nothing away from those players who enjoy the current system and will add far more interesting dynamics to this heretofore rather poorly implemented skill line. Thank you for your time.