Yes, the new powers, spells, perks, and transformation are pretty damn cool, but one aspect takes something away from the "immersiveness". We all know that in vanilla skyrim when you reach stage 4 vampirism you are attacked by all NPCs on site. Okay, so that doesn't sound too great, especially because stage 4 vampirism isn't even that strong, but this aspect forces players to think as a vampire. But more importantly it forces the player to do what all vampires must do... It forces the player to feed.
IE: when you are about to venture into a dungeon, cave, ruin, etc. you may allow your self to get to stage 4 first, seeing as you'll rarely encounter a non-hostile NPC and the boosts and spells might come in handy. But when you leave the cave you don't want to attract a large bounty and what not so you must stealthily sneak into a town and feed.
Basically you have to think about how much you starve yourself and weigh how much you need the strength or not, causing you to balance it out by feeding often.
But with the addition of DG you no longer get attacked by NPCs unless you use your transformation, and when you're not transformed, why not have the extra strength of being a stage 4 vampire? It really takes something away from being a vampire. It takes away the danger, risk, and strategy.
What's your opinion on the whole "stage 4 vampire" thing?
Personally I wish they would've buffed up stage 4 a little bit while keeping all NPCs hostile, and added the transformation in as the vampires "big scary trick up his sleeve"