Manchester United performance against Manchester City wasn't good, both of them play very bad, Manchester United was lucky they got 2 big chance in near end of the match. If not, they would lose against Manchester City.
I'd say Manchester United hasn't changed, they only have few good players like Amad, Mainoo, and Mazraoui, other than that, they're the same.
Although Manchester city are currently in a bad shape but against Manchester United they put up a good performance maybe because it is a derby, with this Manchester United also played well. For me that was the game I saw Amorim style of pattern been played out perfectly. I think even if they had lost that game the manager would have been pleased with the overall play, so the saying that they didn’t play well I don’t agree with that. If they were able to bring that Manchester city game consistency to their last two games they would have done better on those games.
As for the improve players under Amorim I will say the three players will be Amad, Urgate and Mazourrai. Mainoo hasn’t been himself to me and is slow. He cost them the defeat to Bournemouth last weekend