Originally Posted by Zarex
I say keep RDJ as Tony Stark and bring in a new character to wear the armor. You could retain Downey in a smaller role as a grizzled mentor and weapons designer to the new IM. If you want to keep the Stark name, Tony very likely has a previously unacknowledged adult son (or daughter) kicking around somewhere in the MCU.
So...Iron Man 4 would be titled "Iron Man Beyond" then?