Two words: MILLENNIUM FALCON!
As good as it would be to see Luke, Han, Leia and Lando again, I think they're all too old to have any major parts in the new films. And I seriously hope Disney are sensible enough not to do the youthening a la Jeff Bridges in Tron.
Perhaps Luke could be on the new version of the Jedi Council? That could work.
R2 and 3PO will have to be there, but I hope they can stick to physical versions and not the flying CGI slapstick comedy versions
Vader should not be there - unless it's in some kind of flashback, maybe he had a secret apprentice that will be the new baddie?
It never occured to me that the Falcon might or might not be in the new movies. I guess it depends on who the main characters are going to be. It would certainly be compelling if the Falcon was sacrificed at some point. It's certainly been through a lot.
The thing about a possible Vader secret apprentice is that that was what Starkiller was. So I agree, secret apprentice!