Eyes of Nine
Everything's Fine
One thing is that the Superhero genre doesn't really support zero to hero path progression. It's more like nothing to awesome singularity event. D&D's level based system wont' work with supers I don't think.
You also have to ask which version of super-heroes you're trying to emulate. Video game supers definitely level up. Comics supers less so, but there's so many exceptions (Iron Man's new gizmo or suit, new clever uses for Spider-man's webbing or Johnny Storm flames, etc) that I don't think it's an issue.
Mutants & Masterminds was the first time I saw a game that could emulate Captain America being able to survive a fight with the Hulk or Thor or Superman, and it mostly had to do with feats. D&D has feats.