Yep,it's intersting that a Volkharing Vampire Master can kick your a$$ at the day light.But unfortunely for the player,comparing the power to a Volkharing it's like 1/15 of it's power.
Probably because the character is not even 1/15 the age of the Volkihar Master...
Making the character advance to stronger stages as he/she starves? Completely backwards in my opinion.
It actually makes sense. When you consume the fresh blood of the living, you're suppressing your Vampirism, therefore becoming more mortal and less undead. You gain the ability to infiltrate mortal society, yet you lack most of the powers inherent to undeath. When you forgo feeding, you're embracing your undead nature. As the blood in your body begins to stagnate, your body begins to transform into a fully undead monstrosity, granting you greater strength, resilience and powers, while making it plain for all to see what you are. "Dracula" would be a fully fed Vampire, while "Nosferatu" would be a fully undead Vampire.
They did make some mistakes with Vampirism in Skyrim, however. For instance, when you feed, you should be able to choose how much you want to feed, which determines which Lvl of Vampirism that you revert to. Going all the way back to Lvl 1 is annoying, considering it doesn't have many powers at all at that level. Plus, in order to play a Vampire character effectively in Skyrim, and not have it be a COMPLETE pain in the ass, you have to be a stealth build. Trying to sneak up and feed on people on a heavily armored Warrior with no sneak isn't going to work.