I tend to avoid creating characters with any sort of rigid process or framework; they are all born of individual collections of ideas, most stolen from elements in reality or aspects of peoples' personalities. I find it makes them more credible and "human", but more often than not they simply do not fit well within most roleplays. It does not help either that they are all anti-villains or anti-heroes, which can be readily disruptive to some efforts. Speaking of, I only just recently have begun playing a "good" character.