Gothic 1 & (less so) 2
They don't end up really "destroyed", they still are fine game, but the clumsy keyboard-only control scheme, and the unintuitive inventory UI almost ruined G1, IMHO... what's worse is that it wasn't even really justified from a design point of view, just a developing time shortcut; the game was recent enough to have seen previous examples of mouse&user friendly RPG UI done well, and even a basic Diablo-like interface would have been enough
The default control scheme for Gothic 1 was horrid but I was able to over come it using an external profiler to map the keys to an game pad.
The previous two games are sabotaged so that the only comfortable control scheme is with a 360 controller.
Huh? Why would you play DX2 with a gamepad?
The interface was a little sloppy and the targeting reticle was the size of a quarter, but I wouldn't even consider using a gamepad.
Anything that involves using WASD to steer around a 3D character or through an 3D environment I try to map to my game pad otherwise my hand cramps into WASD Claw.