I really wish that Lichelle Marie would come back. She was one of my favorite "barbie doll" pornstars (i.e. tall, blonde, tanned, toned, with big fake boobs). The Brazzers scene where she gets fucked in the shower room still turns me on despite the fact that I've watched it many times.
Keri Sable is another one I wouldn't mind seeing again, although she retired so long ago she wouldn't be able to pull off the "barely legal teenage nymphomaniac" image anymore.