StingingVelvet: Bloodlines for sure.
Vampire in TES is fun but limiting, and since the game isn't specialized for it you never really feel like an awesome vampire. Bloodrayne has the vibe but I dislike the gameplay, mileage may vary.
Don't you usually play without mods tho?
Vampire Embrace:
- Most NPCs still hate vampires, but you can bribe or persuade them to talk to you or allow you to drink some of their blood. Drinking a little each time gradually causes them to receive an increasing amount of pleasure from your bite and raises their disposition towards you. Eventually they become a Blood Thrall and can be used as a companion or asked to accept the Embrace. Drinking too much of their blood at once or within too short a period causes them pain and can kill them (tho you can save a dying NPC with the Embrace... but they will be unhappy about this at first).
- During combat, you can drink from most humanoid opponents if you can deplete their fatigue with hand-to-hand combat. This is animated even in first-person view, complete with blood trickling down their neck. You can drink them dry or force them to become a blood slave. Blood slaves gain addiction to your bite over time and can be released from your control, become willing servants, and be asked to accept the Embrace.
- You can build an army of vampires, thralls, and slaves. Embraced NPCs gain the benefits of vampirism and can be powerful allies, but they will not follow until you are equal or greater to their level.
Vampire Hider:
- You can hide your vampirism by wearing a helmet. Yay! :)
Bloodlines is fun, and I like it, but Morrowind + Vampire Embrace kicks its ass. ;)
Vampiric Hunger and/or Vampire Realism can complement VE but might annoy the crap out of you unless you take the time to configure them to your liking. Sadly, I'm not aware of any Oblivion or Skyrim mods that do what VE does (tho there are some impressive vampire mods involving powers, companions, etc).