It's the spine that needs sorting. De Gea has made too many mistakes now and we should have reacted sooner. If we replace him adequately, it would be, in my opinion, potentially the biggest margin of improvement we could possibly make. Bigger than signing a centre back, centre mid, right sided forward, striker or any other position people believe we are desperately in need of. Henderson should be given the rest of this season as first choice. If he isn't up to it, then a decision will have to be made. Persist with him into next season, or enter the market. Either way, De Gea is not the answer.
Maguire is one of the better centre backs in the league. I think we can win a title with him. Lindelof is good too, but I see him more as third choice in a squad that competes for trophies. A fully fit Eric Bailly doesn't exist, but it would be great if we could find that type of player in the Summer window.
I'd like to see us pursue another central midfielder. A Matic replacement. Fred and Mctominay are a different type of player and are not suitable for this role. A Michael Carrick clone would mean we could be a bit more assertive in the bigger games especially and partner Pogba or Van de Beek, with him. Essentially removing the need of having to play both of Fred and Mctominay.
A centre forward to replace Cavani is still another 18 months away, I believe. I think we will make a big play for Haaland, though obviously there is no guarantee we will get him. Martial is fortunate to have this period of time to rejuvenate himself. Can he get back into last season's groove? Perhaps this is his final chance. As an aside, maybe somewhere in this next 18 months, Greenwood will get some form of audition or opportunity as a number 9.
Thinking about it, the real hard decision for us is whether we should sacrifice the exciting signings in return for something a bit more boring, but perhaps more worthwhile. Potentially a goalkeeper, centre back and defensive midfielder. Possibly a backup right back if the funds are there and the club deem Williams/Dalot/Laird not good enough or ready yet. Grealish and Sancho are quality players, but Hannibal and Amad providing depth and competition to Rashford and Greenwood, whilst allowing us to strengthen elsewhere might not be a bad ploy.