Most people don't know non A-list actors like that, believe it or not. "That guy from..." is purely a visual thing for most. But, for the fans, it'd be nice to have someone else, so we can create this fictional fictional world in our heads.
Guy Pearce is a cool pick for skill, but I'd like someone who is capable of carrying their own movie, and Pearce is already the bad guy in Iron Man 3. I'd prefer to get that awesomeness of the casting the Joker in TDK again. Someone who's not always a villain, someone who is relatively young with A-list potential and some heavy drama roles to match their action ones. Someone like Jake Gyllenhaal, I guess. DiCaprio would be cool too, I think, but he does seem to look weird fake-bald. John Hamm sounds cool, but I doubt even this project would be enough to get him into the superhero business.