Gundogan looks to be the only main CM signing we may realistically have. If it's made certain that his back injury won't recur, and was a one-off thing, then it could be a really good deal for us. Plus, he'd suit our game, starting attacks from the Central Midfield, which we sorely lack. But if that injury has chances of recurring, then yeah, not so much.
As for Carvalho, young, raw, true, but other holding mids aren't exactly available easily, so only one for us I guess;; Fernando will be courted by quite a number of clubs - I'd have liked to see him here, but that won't happen. Alex Song transfer won't happen.
Kovacic, I still feel we should move for him. He's very, very unsettled at Inter, and not getting consistent games, which has resulted in the dip in his performance. Putting him next to a holding mid, and told to initiate attacks, I still feel the best can be brought out of him.. There are rumours that Moyes is going for an improved bid for Fabregas. Clearly not a case of 'Once bitten, twice shy.' Why Barca would want to sell him, I have no clue, but apparently we're in the running to bid for him :\