I've seen Morrowind Overhaul, and it looks amazing, but I keep waiting for the second half of that mod, the game experience pack, to be completed before installing the whole giant thing and experiencing Morrowind anew. Otherwise I feel like I'd be wasting my life, since I'd have to play Morrowind again anyway once the second pack came out... But by the looks of things, that won't be any time soon, so maybe I'll give in within a year.

But for me, at least partly, nostalgia must play some role, since I played Morrowind before Oblivion even came out. It definitely has some real, objective, features going for it though. The superior loot system, the more varied and atmospheric locations, more armor/weapon/skill variety, etc.