payn
Glory to Marik
To go along with both the current alignment mechanical discussion and bring it back to the experiment in the OP, I think there is a lot of potential in alignment restricted prestige classes. I always thought the Paladin should have been a PC, though I know the popular take is that Paladin is generic and not specific. Though, if base classes were stripped out of alignment it allows for an alignment free game, while giving PCs a way to bring it back mechanically. The bonus is that going alignment restricted is now a choice the character makes later in their adventuring career instead of a beginning default.