With the current performance of Manchester united no one can tell if they will improve in performance in the long run but if it is with what they are playing now, I don't see them in the finals. Tottenham is also unpredictable. I think it is too early to conclude.
Atalanta surprised everybody last season and they were underrated but I don't think there's going to be another suprise this season. Tottenham isn't looking like they're going to win anything or they might be the surprise this season by winning a trophy through winning the Europa league but as I'm writing this, it sounds not possible to be because Tottenham aren't a serious club. They're too comfortable where they are and not try to win something for their fans. Manchester United are so unpredictable but they have a chance of winning because they get lucky always and they don't deserve that luck most times because of how badly they have use to play.