The metaphor is the story, not the character.
The characters are, by their nature, archetypes that can serve different metaphors.
If there's ever a character who can only serve one metaphor, I'll probably tell one story with that character and be done with it.
The Hulk is rage personified, just, "I don't like something. Break it." And that's a great concept for a seven- or eight-year-old.
I like superheroes. I like the drama of it, the stirring, larger-than-life aspect.
Maybe I had a 'secret identity,' but then when you think about it, don't we all? A part of ourselves very few people ever get to see. The part we think of as 'me.' The part that deals with the big stuff. Makes the real choices. The part everything else is a reflection of.