5. Viggo Mortensen
Viggo Mortensen has shown an aversion to starring in big budget movies ever since his breakout in the Lord of the Rings trilogy. Although he was in a host of acclaimed following that trilogy, Mortensen has been a little quiet in the last few years and a role in a Star Wars movie would be a welcome return to prominence for Mortensen. He has shown an ability to play a multitude of roles, from Aragorn to a member of the Russian mafia. He would be equally good as either a hero or a villain although my preference would be for him to play some kind of brutal imperial officer.