No doubt Manchester United's forward looks much better this season compared to last season's mess, but the defensive line still lacks that composure in defending goals from their opponent.
Amorim should rather change the 3-4-3 formation and think of a better formation that will suit the team and give a try; As we can all see, the premier League is a very competitive league which he might not succeed with the formation this season. I could recall clearly how Chelsea struggled during the season with Conte introducing this same strategy, and it was a hard one for them to win matches and stay top as one of the big team in the league.
Manchester United's attacking position is indeed better now than last season, especially since they successfully recruited Sesko as their striker, complementing their attack line, which was previously often considered lackluster and overly reliant on one or two players.
However, their defense seems quite lacking... as seen in previous matches, their defense has often been less than effective in blocking opponents, especially when facing fast transitions, which often leaves their defense vulnerable.
Unfortunately, Amorim hasn't considered changing their strategy despite this situation, preferring to stick with it and hope it continues to work. It's a bit annoying, but Amorim won't change his principles.