So about fifteen months ago I let my ESO subscription lapse, not because I hated the game but because I needed to not spend the money. I promptly moved to an area with really lousy internet (AT&T Uverse, bottom tier) at which point I suddenly became a heck of a lot more interested in games that didn't require an internet connection.

So it wasn't until last week that I logged back in (after waiting, um, a day and a half for the game to update, ugh) and started taking a look around. This is what I've found.
DISCLAIMER
I'm not a particularly dedicated gamer. I like logging in and playing my characters, I run mostly solo content with occasional pick up groups to go through dungeons, and if a hard-core PvE or PvP'er looked at my gear they'd probably double over laughing. So, you know, don't expect any insightful discussion of game mechanics. I don't math well. Don't expect this to contain a single spreadsheet or calculation in it -- it's just me comparing my memories of 15 months ago with the game now.
FIRST: NEWBIE COLDHARBOR
There has been some significiant streamlining to the newbie Coldharbor starting stuff, basically with Lyris just wandering by, saying "hey, Imma break you out now" instead of the prophet's psijic projection showing up and going all "heya chosen one I have a task for you." Moslty I think the streamlining is a good thing. I do miss the days when you could choose your starting weapon, but that had gone away even before my prolonged absence. My new sorcerer didn't find a freaking destruction staff his entire time in Coldharbor and it pissed him off mightily. He eventually picked up a restoration staff in the Coldharbor delve but it wasn't the same.
Anyway. It was mostly the same as I remember it but they shaved it down a little.
SECOND: RETURN OF THE STARTING ISLANDS
To be fair the starting islands never actually went away, but they got shoved into a corner, and I always felt that was a mistake. I was very happy to see my Breton character, after leaving Coldharbor, waking up on a boat moored at Stros M'kai. I loved those freaking islands, and felt it made sense story wise to have them. I always wound up going there right after leaving Coldharbor anyway. I'm glad they're back.
THIRD: EVERYTHING IS ALWAYS MY LEVEL
At least, that's what it looks like. There are no longer white/red/blue/yellow/taupe/fuschia/argent colored monsters. This is, I assume, the level scaling mechanic that allows everyone to group with everyone.
I really, really like this. I like exploring, and the zones are large enough that it was very easy to outlevel content. I hate outlevelling content. I don't know if there is still some kind of level/power differential mechanic in place, but at the very least it no longer looks like I'm slumming when I explore, and that makes a heck of a lot of difference. It means I don't feel bad about going back to zones I really enjoyed and just romping around in them (i.e., Coldharbor, Rivenspire). I really like that.
FOURTH: BLAZING SPEAR SORT OF WORKS, BUT IT'S NOT AS MUCH FUN
I play two Templars. Blazing Spear was one of those abilities that serious Templar players told you not to use because it had a very unfortunate glitch where sometimes it would "lock in place" and prevent you from doing anything, meanwhile everything killed you. I was not a particularly serious Templar, and my counter was "yeah, but when it works it's a lot of fun!" And it was: when it worked, it picked you up and zoomed you into the enemy really fast. Sometimes the way it navigated around obstacles was hilarious (once my Blazing Spear took a hard right turn to take me down a flight of stairs before continuing on its path toward the now-confused target). And did I mention it was fast?
Well, they fixed the thing that made it completely unreliable in combat, but it doesn't feel the way I remember it. There's a pause before it goes off, and I sort of lazily rise into the air and meander over to the target. It feels like they replaced a somewhat unreliable sports car with a more reliable, but definitely slower pickup truck.
All in all, it's probably for the better, since I haven't had it glitch once in the last few days, but I miss the old "zoom."
FIFTH: SORCERERS SEEM EASIER TO PLAY
I started ESO as a sorcerer, and I wondered why they made the game so flipping hard. Then I started playing other classes and realized it wasn't the game.
Sorcs were very fiddly classes. They still are, probably, but not nearly as much!
My average combat scenario, back in the day, went something like "Oh, my storm field just dropped better put it up again, wait crystal shard procced? Dammit! missed the timer GAH I ACCIDENTALLY UNSUMMONED MY DINOSAUR annnnd I'm dead."
I still don't catch my crystal shard timers (but now I have a plugin for that) BUT I don't accidentally unsummon my Clanfear any more, and now when I try I get healed instead. Much better result! Also, I can have my pets target specific monsters instead of relying on them not to aggro other groups (never rely on a Cleanfear not to aggro other groups!)
Sorcerers still seem like the fiddliest class to play, but not nearly how they used to be.
SIXTH: WAIT, THERE ARE OTHER DESTRUCTION STAFFS?
Once upon a time there was the fire destruction staff. There were rumors of other staffs, but you sure never saw them in game... except for my characters, who thought Lightning staffs looked cool. People laughed at my characters. A lot. Because while they did look cool, they were pretty useless compared to fire destruction staffs.
Staffs have been changed up now, and lightning staffs get damage bonuses for aoe attacks. And I'm seeing them more in game.
Haven't seen many ice staffs though.
SEVEN: HEY, THE DUAL BLADE BUG APPEARS TO HAVE BEEN FIXED
Once upon a time there was this really nasty Dual Wield bug where the first skill, which was a channelling attack, would get "stuck," not letting you get out of the animation or do pretty much anything unless you hit escape twice (to bring up the main menu, then close it again). This was really nasty in a fight. My nightblade hasn't suffered from this problem once since coming back, so I guess it's fixed? IT IS GLORIOUS.
EIGHT: AUTOMATICALLY STORING CRAFTING MATERIALS IS WORTH THE PRICE OF A SUBSCRIPTION
Seriously, the ability to harvest crafting materials and have it automatically go to a special bag shared by all your characters is worth the price of an ESO Plus subscription. In fact, when I realized you could do that with an ESO Plus subscription, I re-subscribed. YOU DON'T UNDERSTAND WHAT IT WAS LIKE IN THE DARK TIMES.
NINE: CRAFTING IS HARDER? ALSO, WTF, SO MANY MOTIFS
I don't know if crafting is actually harder to advance, or if I'm just looking at the past through rose colored glasses. I seem to remember though that it was possible to get crafting xp from refining materials. Not any more. And... there are a lot of different motifs floating around these days. More than I can keep track of. That's not bad or anything, just different.
Anyway, that's one observation per Divine, plus Talos (ITS NOT THE FUTURE YET) so I'll end it here. Overall I approve of everything I've noticed so far, except for the refining materials thing, assuming I remember it correctly.