10. Adam Warlock
Adam Warlock is a man-god who was created by a group of scientists called The Enclave. It is after denying his creators and having a confrontation with Thor (crossover, anyone?) that Warlock decides to travel into space. in the comics, he allies himself with Gamora (yes, from Guardians of the Galaxy) and Thanos to oppose the Magus.
The Magus ends up being a future version of himself, so he alters his own timeline...needless to say, it goes on to be a great story. Adam Warlock is at the heart of the current Marvel Cinematic Universe.
He is a natural fit, a great character, and we are willing to bet he would be a money magnet at the box office as well.