4. Ms. Marvel
Major Carol Danvers is one of the strongest women in the Marvel universe, with strength comparable to Iron Man. She has immense strength, is practically invulnerable and indestructible, can fly and can absorb and discharge blasts of energy. She acquired these powers through an accident that fused her genes with alien Kree genes. Shortly after acquiring her powers she became an Avenger. In addition to her superpowers, she is an expert pilot, Major in the United States Air Force and former C.I.A. agent.
Why does she need a miracle? Female superhero films have historically performed poorly at the box office. Tank Girl, Barb Wire, Catwoman, Elektra and Aeon Flux were all critical and commercial failures. These failures can at least in part be attributed to poor support by the studios in creating such low quality films. Whedon made a very serious attempt to make a Wonder Woman film, but the project was knocked back by studio executives. Including Ms. Marvel in the Avengers would give Whedon the opportunity to use a similarly super strong female character, but it would no doubt come against pressure from Marvel executives. If Marvel studios are willing to put in the time, effort and money they could make Ms. Marvel work.