Your point that we can't relate to anyone but Mr.Justified is untrue. It's simply so pervasive that it has taken on the appearance of universality.
Dream of the Endless, arguably more characterized then any superhero, was a disgustingly vain man, going so far as to once hold a women in hell for 10,000 years because she wouldn't go out with him.

As for why video games lack character development, well honestly that's just shit design. It's nothing to do with anything you mention. Two prominent examples are Vtm Bloodlines and Gooosebumps: Escape from Horrorland.
Both allow you to explore all the characters as deeply as you want, or as little. For instance in Horrorland you can trace the lychanthropy between stores as it passed through the village, or in Bloodlines the complex web of relationships between the characters of Santa Monica (oh, and the bounty hunter boss guy has herpes).

In short, you kind of wasted 4 pages. It's cool though. I sometimes run at the mouth as well.