Zexion is really cool.
Vexen is like a whiny old man, but I guess this could make him a comical character.
Lexaus is cool also, and his image really fits his fighting personality, strong and a tomahawk.
Larexene I guess I would say she acts kind of bitchy but in the end she makes an excellent sidekick for Maruliuxia.
And Maruxlia hmm... believe it or not but when I first played COM I thought he was a she!