Cillian Murphy as Reed Richards/Mr Fantastic
Cillian has that genius look and is a damn good actor,he has already played a comic book character before(Joanthan Crane/Scarewcrow in the Batman Begins),I would like to see him play a hero this time around
Dakota Johnson as Sue Storm/Invisable Woman
Dakota is both beauitful and good actress,I would really like to see her try a character like Sue Storm I think she can do it. She may seem a little young for Susan,but Dakota can play older characters just like Jennifer Lawrence and Margot Robbie do. Also Sue was originally about 10 years younger than Reed,before they made changes in the comics
Brett Davern as Johnny Storm/Human Torch
Brett has the look and can pull off Johnny's cocky Attitude(As seen on Awkward)
There is not much to say Brett is Perfect for the role
Kevin Durand as Ben Grimm/The Thing
Kevin played Fred Dukes in Origins Wolverine,but I think he would be much better fit for Ben Grimm,he has the look,the size and the attitude to the do the role justice
Sharlto Copley as Victor Von Doom/Dr. Doom
Sharlto has played many villainous roles and is an excellent actor,that is why I think he woud be perfect as Marvel's top villian