Winks, Foden, Cook are certainly 3 who we should be looking to get in and around the squad and padding out with the experience of Henderson and Dier.
Though I do like Will Hughes and think it'd be harsh if he never got an England call up. Looks to have started the season off very well with Watford too.
Foden's showing that he's probably going to be a star player, but I think its possibly better to leave giving him a full cap for a little while - he's only made about 6 appearances for ManCity, he's only 18 and has played for E u18's and no higher.
No harm in him (and probably a few others) training with the squad, getting to know them etc so that when, inevitably he's called up having played more for ManCity, he has a better chance of a decent debut through knowing more of the squad and how they play.