The one thing that bugs me about people always pointing to Catwoman, and Elektra as reasons not to do female lead superhero movies is the fact that they apparently just were not good movies. I haven't seen them to judge first hand, but I don't think I've ever heard a good thing about either of them. I think that the Hunger Games proves that if you have good sci-fi action movie with a female lead, people will go see it. I really think there is enough awareness now that if somebody made a good Wonder Woman or Black Widow movie, people would go see it.
EDIT: I just remembered more proof that people will go see a female lead action movie, if it's good. The Alien and (first two) Terminator movies. I really think if a movie is good enough and the marketing is good, then people will go see a movie with pretty much anyone in the lead.