I’ve been thinking about Scott’s post in which he talks about attitudes towards character development, but I think that he may be conflating two different things: approaches to playing the character, and the type of character one plays. I think they’re related, but are not the same thing at all.
Scott’s List was:
1) hero fantasies
4) real life
and although he didn’t number it
5) different as possible from oneself
Heroes, Ditzes (or Eccentrics, as Rachel prefers) are, I think, types of characters, Oneself and Competency are approaches to playing a character, and Different as possible from Oneself is a motivation for playing a type of character.
For instance, one could easily imagine both playing a Hero because it was different from oneself and attempting to play the Hero in a maximally competent fashion.
Actually, the topic of categorizing styles of play, motives for playing, and even types of characters has been chewed over at great length in places like the rec.arts.gaming.frp.advocacy newsgroup and elsewhere.