Absolutely, he could be. Hence the large sell on clause. Don't think he'll bloom here though as he won't work in a 4-4-2, probably needs a more free central midfield role than having to get up and down the pitch.
If he leaves, I hope he goes on to do well. Another victim of being over hyped at...
Yes they would if he's offered a new contract. Key for me is that we get a big sell on. I'd be okay with a small fee but large sell on in case he improves a lot.