Manchester United may not have made many changes, but I wouldn't underestimate them. Last season wasn't a good reference. When Amorim took over, the team was already languishing in the Premier League, so they shifted their focus to the Europa League, but unfortunately, they failed there as well.
So, next season, Amorim will certainly build the team according to his wishes, and that's worth looking forward to, because I think anything is still possible.
Amongst all the big teams in the Premier League they are the only team with he least number of signings so far but looking at the areas at which they strengthened which are crucial areas in the squad and they may still sign more players just before the transfer window will close in September. Amorim might do well for himself this season.
I do not have high expectations for Manchester United this season, yet I am very confident that they won't be a poor as they were last season. If you are a good observer, you will understand that Manchester United squad started improving towards the ending of the season. Even if they were not actually winning matches, they were playing coordinated and understandable football unlike from the beginning of last season. So if Manchester United coach keeps improving the team with the few new signings that he did, there is actually good chances of Manchester United improving this season. But being in the top five is what I am not so confident about because there are many good teams in the English Premier League presently.
So, even if Manchester United is unable to end at the top five of the English Premier League table. They will still become portable in the top 10 and not anywhere close to 15 position they ended last season.