Originally Posted by cherokeesam
RDJ still has at least one more Avenger film after AoU. But I keep coming back to the Extremis Armor: if he builds a version of that, or Bleeding Edge, the suit essentially becomes literally a part of Tony. It's possible that Tony won't be able to integrate Jarvis into that suit (Tony is essentially a cyborg with that armor), so morphing him/it into the physical form of Vision would be a great way to keep Bettany's voice and personality around for future Avenger films.
And based on everything that has happened, I think Extremis and Bleeding Edge may be what's next up for Tony.
Plus, an armor that lacks AI and is a literal part of Tony would make ALOT of sense when going up against Ultron, who would just as easily hack his suit and take control of him, like Vanko did to Rhodey in IM2.