I prefer Shadowbane. Hardly anyone remembers that game though. I haven't enjoyed an MMO since.
Still have a bunch of screenshots from my short but nice Shadowbane time. Well nowadays it looks ugly, but I loved my badass minotaur ! Now it'sonly some shots in my gaming tourist directory (screenshots of all games I've tried, mmo and all)
On topic, having player WoW up to level 60 before the first addon came (then I left, cursing this game forever), I think the interface point is a good one. Wow's interface is a masterpiece both in ergonomics and customizing. I am not saying there isn't better out there, but I remember
enjoying going through it.
And at last, I like how monsters aren't levelled (I know, this was easy), although I wouldn't like so clearly separated level zones like in a mmos. Monsters of various levels should be mixed up a bit, forcing you to be careful when in the wild.