Improved animations. The facial animation is more lifelike.
Improved NPCs. They behave and socialize more realistically. They laugh, joke around, physically interact.
A whirlpool in Whiterun. (Weird addition, but hey, its a dream.)
Game version was 2.1
I don't think the real Bethesda would be that wonderful. Would they? Well. they did hint at improving the main game with DLC.
Most of this stuff would easily be next-gen features.
Curse you, brain!