We still use the class limits... pretty much. Besides I do not find dwarf wizards and halfling paladins interesting or innovative. But the level limits either never come up in our games or get really annoying when one hits that. And the xp modifications, I never really liked them...
Player's Options books sholud be used as DM's options as you mentioned, but I think that they don't deserve all the bashing since there are quite a few good ideas and mechanics there. When using these, we limit the race and class modifications and do not allow metagamey options like modifying the rolls by using CP's for example, but a being able to make few customisations is cool, and the spell point system fits the feeling of preserving/defiling in Dark Sun.
Player's Options books sholud be used as DM's options as you mentioned, but I think that they don't deserve all the bashing since there are quite a few good ideas and mechanics there. When using these, we limit the race and class modifications and do not allow metagamey options like modifying the rolls by using CP's for example, but a being able to make few customisations is cool, and the spell point system fits the feeling of preserving/defiling in Dark Sun.