My group tends to do two types of game settings: Star Wars and some kind of Superhero game. While I think the engine is flexible enough that you could adapt it to any setting - you could do a Doctor Who game, Ghostbusters, 007, a Giant Mecha anime game - with relative ease, doing a Superhero game seems to be a bit harder. Well at least from my 15 minutes of thinking in the shower.
Go look at the endless pages on pages for powers in HERO, plus the assorted add ons and minuses to go with those powers. That's a pretty diverse power set. Sure The Force/Jedi-ness will cover some of that, but coming up with an engine that will do Superman and Ant Man and all the crazy arrows that Green Arrow can pull out - that's going to be quite a page count. What do you guys think - viable campaign setting? Or just too much for the engine to handle?