This is tricky...
Keith?? Not a chance.
Cassi? Got backdoored, did not have a chance to save herself. The feud against Rachel would be interesting...but do we really want to bring back someone who may not only be against Rachel, but by default Rachel's ALLIANCE of J&J?? Hmmm.
Dom?? Totally got screwed by Dani and yes, prob deserves to come back on that basis. BUT....would he come back on fire to play and ready for revenge?? Or would he crawl right back into Dani's lap?? I do not like Dani's game play and do not want to bring back a pawn for her to use again.
Brendon...oh please, no! Although his edit on the show was the "knight in shining armour", we haven't seen his controlling and near abusive side to Rachel on the show, so America could vote for him.
I am starting to hope that we don't see ANY of them come back.