Tyler Mane is a good choice, since his work in X-Men, Halloween and H2 was pretty good.
Ian Whyte was a good stunt man for the Predators in AVP and Requiem
For a future predator movie, i'd like to see them have an ensemble cast like they did with Expendables and Predators, Sylvester Stallone is a good option, i'd like Schwarzenegger to return, maybe Samuel L. Jackson, Mickey Rourke perhaps...
But with Schwarzenegger reently announcing a "predator remake", they might recast everyone completely