In their current form, vampires aren't exactly viable, except for niche builds like ganking and farming builds, and I am rather sure the ganking builds are going to be one Oblivion of a problem in PvP but I don't play that so I don't mind that so much. However, like before the Vampires will be best when they don't feed which feels like a mistake, the main problem for this is the 20% increase to non-vampire skills, which makes only short, bursty options viable or full vampire builds, which isn't really possible with the current tool kit. While this skill line will surely be great for overworld content, it's going to do rather poorly in any dungeons as a result. Of course, Vampires need a drawback otherwise it will be like before where there is no reason not to be a vampire, except for the skin it forces upon to you.
So instead I propose that we keep the increased costs to skills, and lower health rate. But reverse the rates at which they happen, and lower the time it takes to lower the stages from not feeding to about 30 minutes per stage, and make double bloody maries just slows the timer in half for a short period, say 30 minutes instead of raising the stages. At stage 2 and lower some NPC's won't talk to you. This will force the players to feed often in order to prevent them from getting the detriments of the lower stages, losing passives, getting weaker. However, as the player feeds more, they take more fire damage, and more damage from silver/holy, but still have the bit of skill cost increase and health recovery detriment. And finally, feeding is a rather monstrous thing to do, I am sure even criminals would report it, if just to get some heat off their back. If there is any witnesses during the feeding, whether friendly, neutral, or hostile, you will get a bounty for it. Thus requiring stealth.