Re: Phase II and the UK
Personally, I'd *like* to see Britain (and other countries) play a larger role in the MCU, and make the MCU more global than the New York-centric comics universe; but I'm reasonably sure they keep going back to Shepperton for economic reasons and a healthy working relationship with the studios there.
But there's no doubt that Marvel Studios really likes to go for British/European/Australian stars when it comes to casting calls, so I wouldn't be surprised to see some traditionally American heroes/villains be expatriated to other countries. I've long said that I'd actually like to see Hank Pym become a Brit.
THE COTTON AVENGERS
...They move like slick cotton on oil.