With the quality of players Leverkusen currently has, it will be very difficult to compete with Bayern Munich, as Kompany's team is much more developed. Erik ten Hag arrived at a time of rapid development, but several of Leverkusen's potential players have left with Xabi Alonso's move to Real Madrid. The most realistic option is to fight for a top-three finish, as fighting for the title against a much superior Bayern Munich is a significant challenge.
A lot has been speculated concerning what the performance of Bayer Leverkusen is going to be their season and some people including myself is of the opinion that the Leverkusen team will have challenges competing with Bayern Munich team in the league because they are looking better than them in terms of the squad depth but then I think it not good to draw conclusions yet when we haven't seen the performance of the team under the new manager Ten Hag I believe if Leverkusen team finds it difficult to withstand other teams in the league they will regret why they let their players go.
I don't think that they were happy in letting those players go, just that they are not as capable financially like Bayern Munich or some other team in the German bundesliga, and besides you don't keep and unhappy player in the team, so selling most of their key players is entirely not a bad idea, where I sees problem is if the money is not reinvested into the team.
Talking about the manager Eric ten hang, I will not start passing verdict on him yet because the season is just starting, after the first ten games, that's when I can say if he is doing well or not, because as we all know, Manager's, especially new ones that is just coming into the club needs time to pass his playing system or ideas across to his players, so he should be given as much time as possible before I can pass any verdict on him. What most football fans are doing is that they are still looking at his with that sentiment of his Manchester united days, so they are expecting him to fail, but till then I wouldn't pass any verdict just as I have already said.