I have trouble playing the super-evil guy in RPGs. I just get these pangs of emotion and experience mild depression afterwards.

I'd have no problem with a German campaign in a shooter though. Let us play the Naziest Nazi Murderer of all time for all I care, as long as the story is passable and the mechanics are good (I could see "Play as the bad guys!" being used as a gimmick to distract from bland and uninspired gameplay).