We have problems in defense, we have problems in midfield, and, we also have problems in attack. All areas of the pitch are problematic.
Decline of Martinez and Casemiro. I feel like they should've/could've prevented all of the 3 goals we conceded against Brighton, but they didn't. Injuries to Varane, Shaw, Amrabat, Hojlund(until recently), Mainoo, Amad, Mount, Wan-Bissaka(newest one), Malacia...
We should've replaced Maguire this summer with someone more competent who could even maybe be long term partner for Lisandro(if he gets back to pre-injury form), but he was too greedy and it failed. You can't rely on Varane, he's too injury prone. All of our fullbacks(except Dalot) "decided" to get injured at basically the same time, which is mind blowing. Lindelof is a "meh" defender, should be a 4th choice CB at best(probably 5th).
Our midfield has no ball retention ability, whatsoever. They treat the ball like a hot potato(I've said it many times, and I will continue to do that as long as I'm a member of this forum). We desperately needed a press resistance ball carrier, alternative to Frenkie de Jong(Kone, Thuram, Nunes, Gravenberch...) and we got an underwhelming attacking midfielder in Mason Mount, which I don't really understand why. Casemiro doesn't look good so far this season. His legs might be gone, which is not surprising, given his age. Short term thinking from our idiotic recruitment department. Might have to cash in on him and send him to Saudi next summer(if he accepts, which he might not). Similar with Varane.
Mount and Eriksen can't play deeper in a box to box 8 role - don't have combination of physicality and technicality(dribbling, passing) for that. I think Bruno should be phased out of the team - I'm a supporter of the famous locked thread "We'll never win the league win Bruno Fernandes in our team". He has no ball carrying/retention ability and loses the ball way too much, even though he is also the main creator in the team. You can't control games with him in the squad(against better teams at least). He's a player for a counterattacking, underdog, midtable team where he would be the main star with his risky, Hollywood passes on the counterattack. Kevin de Bruyne and Odegaard are superior players, probably even Maddison. I would rather have all of them than Bruno.
Conclusion, need more youth/legs/grit in the midfield and more press resistance, ball carrying, ball retention ability.
About the attack, we have only 1 striker at the club(Hojlund) who is very young, talented and just started playing recently, something like 90 minutes in total. I don't consider Martial as a professional footballer anymore, after his contract ends in the summer he's done(at the top level at least). Turkey, MLS, Saudi Arabia...or retirement.
Our two main right wingers are unavailable. One is fighting domestic abuse allegations in Brazil and the other is a lazy slacker who is waging war against the manager and is exiled from the first team squad - "wonderful". Both of them are also pretty underwhelming when they do play and they cost a fortune. Amad is injured, ETH doesn't trust/rate Pellistri for some reason, meaning we basically don't have any right winger available to start at the moment.
Rashford is not in form, got his new contract, too selfish and is strolling nonchalantly on the pitch like a model - not pressing, which creates more problems off the ball. If his work rate doesn't improve, he should probably be benched or sold, even though he's a local lad with connections to Manchester. Rashford is not as good as he thinks he is - he's not Mbappe. He needs to be "reminded" of that. Garnacho is developing, but still too young to start and make a serious impact, needs more progress and development.