Psion
Adventurer
I voted "as powerful", but should add the caveat that I am tolerant of PrCs that:
- Shore up weak concepts. A common complaint is that some classes would give a sorcerer no reason to stay single classed. That's okay, because the sorcerer is weak AFAIAC.
- Play into a campaign concept I am interested in. I am not above bribery to bolster the shared vision of the world.
Blatant over-powered-ness, I'll boot to the curb, though. I like to keep as many options as possible on the table, and overpowered classes diminish that.
I strongly prefer prestige classes as a method of realizing specialized concepts over creating new core class. AFAIAC, core classes should be flexible in nature. PrCs are all about the schtick.
- Shore up weak concepts. A common complaint is that some classes would give a sorcerer no reason to stay single classed. That's okay, because the sorcerer is weak AFAIAC.
- Play into a campaign concept I am interested in. I am not above bribery to bolster the shared vision of the world.

Blatant over-powered-ness, I'll boot to the curb, though. I like to keep as many options as possible on the table, and overpowered classes diminish that.
I strongly prefer prestige classes as a method of realizing specialized concepts over creating new core class. AFAIAC, core classes should be flexible in nature. PrCs are all about the schtick.