This will be relatively short, but everyone has been speculating on what will happen after the infinity war movies. Some say secret invasion and Hammer storylines. But I think it will be something totally different that will allow Marvel to reset and recast all the characters who are aging or have expiring contracts.
Didn't anyone notice, during the scene in Ant-Man where Scott Lang is shrinking into the quantam realm, you see a quick glimpse of "The Beyonders" on his visor.... you would have to watch it in slow motion, but they are there. Now if you don't know who the beyonders are, look them up. They are basically the beings who started everything in the Marvel Universe, and they decide to end everything. They areore powerful than the celestials, galactus, eternity, the living tribunal and Thanos. And it is Ant-Man who finds them. Introducing the beyonders into the MCU would allow Marvel to recast every character, and basically start over, or do Battle World, with new actors and characters. It would also continue the story of Steve Rogers and Iron Man.
There might have to be some script and character changes, since some of the major characters in the time runs out story and the continuing battle world storyline have their movie rights owned by FOX. But it would be amazing and completely outside the box if Marvel went in this direction. And like I said, it would allow Marvel to recast all there characters.
Again just a thought