Jodi Mayree Rose, a budding author, showed me an article that could be a useful resource for fiction writers that breaks down character traits by type (social, energy, etc.) and then further breaks them down by positive and negative traits.
The site, Superhero Nation, offers writing tips and advice for those writing superhero fiction. By the way, Superhero Nation also has other articles on character development. Most of those are useful for any writer, not just for authors of superhero fiction.