Personally I'm on the fence about the original cast (possibly) returning.
I'm also surprised there's so much ageism going on here - Alec Guinness was in his early 60s when New Hope came out so I guess that means he was 70+ when ROTJ hit theaters? I can't tell you for certain if he was healthy or out of shape 'cause he appeared in all his scenes wearing that cloak! If Mark does come back, he could easily hide his appearance in a similar matter. The possibility of Luke Skywalker for SW 2015 is not that absurd.
Hamill could play Boss Nass with almost no makeup...
Electric 6 Radio Ga Ga
Chemical Romance Welcome To The Black Parade
Beatfreakz Somebody's Watching Me
The Darkness I Believe In A Thing Called Love
Boogie Pimps Somebody To Love
Nightcore Land Of Confusion
Bif Naked Moment Of Weakness
Rend Collective My Lighthouse
Dickies Killer Klowns From Outer Space
Cardigans My Favorite Game
Living Colour Cult of Personality
Limousines Internet Killed The Video Star
Alien Ant Farm Smooth Criminal
Sasha D Russian Girls
Scatman John Scatman