Manchester City, Chelsea, Manchester United, abd Arsenal are also going to buy some players I think. City had already bough three players I think while Chelsea and Arsenal are also making effort to sign more players. If all of them succeed with the players they are willing to sign, then next season will be an interesting season to watch because the competition will be tough.
I expect there will be a huge boost to the City and Chelsea performance next season. They bought so many players and tried to solve their last season problem.
About MU, not really sure on what they're building, but i believe they much more focus onto solve their attacking problem.
As for Arsenal, they look very passive. I expect nothing from them next season. Almost the same squad, and maybe the same result.
Manchester city and Chelsea are going to be strong this coming season though it wasn't that Chelsea was not strong per say but they were not consistent so that makes them look like they didn't perform well but at least they qualified for Champions league next season. I don't really know what to say about Manchester city but I believe they will do better this coming season and as for Manchester united, if they don't sign new players they will still suffer same thing next season unless Ruben Amorim will change the team entirely and that will take him a lot of time.