It's more of rating potential though isn't it. In 3/4 years they'll be in their peaks. I could see Morgan/Cork/Clyne/Shaw/Gaston all playing for their countries and good enough to play in Europe. Likelihood is we won't be in Europe anyway so the question is pretty irrelevant.
I would go with Clyne,Yoshi, Forren, Shaw, Cork, Morgan, Gaston, Lallana, J-Rod, and possibly JWP and Mayuka depending on how they develop. It all depends how whether we can keep hold of them anyway