Incidentally, if you enjoyed Marvels, you should check out Kurt Busiek's other GREAT superhero series: Astro City. I don't care for superheroes myself, but Astro City has been excellent for years.
There's no singular main character. Rather, the city is the main character and most issues are stand alone, or arcs that last a few issues.
The first issue is
FREE at ComiXology.