I think Orton stays, too. His salary isn't obnoxiously high and he is a terrific #2.
Where we disagree is, I think (actually I hope) EJ wins the starting QB job next year. But I wouldn't make it easy for him. I hope the Bills get the best FA QB they can sign, and draft one---at least. And then make the competition for the starter as truly open as it can be. The best case scenario (again, IMO) is for EJ to win that competition, as he is young (but has some starting experience) and has a butt-load of talent. I can't foresee a rookie QB I'd rather see as a starter, nor do I think the Bills can sign a FA worthy of starting next year. I think there are one or two veteran QBs who MIGHT be available who I'd prefer, but I don't see that as likely. But again, I'd make EJ earn it. No handing it to him.