I am not trying to be contrary or a smart aleck, but RDJ's star was fading when he was cast. And I would not consider Evans, Ruffalo, Hemsworth, Pratt, Bozeman, Hiddleston, Holland, or the majority of the new class announced big names at the time they joined Marvel. Yes, some were in movies or TV but not huge. Of course, there are some big names, but I don't think Marvel is overloaded with them. In fact, Marvel has made many an actor a big name after the fact.