5. Franklin Richards
It's about time someone in the X-Men movies displayed some
real power. And if real power is what they want to include, no one from the world of mutants would be better to include than Franklin Richards. The son of Mister Fantastic and the Invisible Woman, Franklin is actually more associated with the Fantastic Four than the X-Men. However, this isn't a problem for a couple of reasons; First, the Fantastic Four movie reboot is rumoured to be a part of the same universe as the X-Men movies and, second, Franklin has indeed been associated with teams such as Generation X, who are a young spin-off team of the X-Men. Franklin is a reality warper. This essentially means that if he wants something to happen, it will happen. He could make something as trivial as an ice cream appear in his hands if he wanted, or he could do something as complex as create a universe - which he has done before... in his bedroom. His power is so vast that he made Galactus (the galaxy-destroying, planet-eating cosmic force who himself controls very powerful heralds) in to his own personal herald. He would take the X-Men movie franchise to new, cosmic levels never seen before and that would be
really interesting.