For right now, I actually really like the look of our potential team. Squad can be improved upon of course, but the main thing I would look at is replacing Carrick with a player just like him just 10 years younger. Not sure who there is for that though. Problem is unless Schneiderlin improves then we dont really have that type so Carrick is vital again.
After that, its fine for this season. We just need to bench rooney and pick Mata/rashford/lingard/mkhitaryan/herrera instead of him depending on formation. Valencia at right back is as good as we can get really at the moment. Smalling and Bailly I think can form a class partnership. Shaw is class at left back, then we have darmian, jones, rojo, tfm and blind as back up there which is very good I think. Up front, martial, ibra, mkhi, with young, memphis, rashford and lingard as subs is good too. Midfield is the main thing. Pogba the main #8, herrera and fellaini that back up is fine. Rooney, mata as the 10s can be better but Mata can be class, just needs to be used. For the 6 its Carrick and Schneiderlin which is lacking in starting 11 considering carricks age.
For next season or the one after, carrick, ibra, rooney, valencia all need to be replaced. So a right back, holding mid, #10 and striker is what we need in the next year or 2. A few promising youngsters can develop there and fill the spots but likely we'll need to buy a few of those.