Sonic Adventure: The controls and camera are Sonic 2006-level horrible! I am now even more disgusted with Sonic 2006 than I was before. If they couldn't fix those God-awful problems in 7 freaking years (or really, just returned to them after doing a lot better in Sonic Adventure 2), they really deserved all the problems they're having now.
Outland: I don't really have much to criticize with this game, but the difficulty curve is pretty high. Right now I have to locate a Guardian Key with absolutely no indication whatsoever as to its location. And this is in the second level. That's annoying.
Castlevania Circle of the Moon: Again, difficulty. I started playing on Saturday, and died before the first save point. Before the first save point! From the Let's Play I'm watching of it, it seems Konami got the difficulty curve backwards, actually, and it really gets progressively easier. Way to go, Konami... *eyeroll* But this is Castlevania, would I expect anything less than obnoxious difficulty? I'm past the first boss now, and yes, it is getting easier with higher levels and more power-ups.