I am sure that Bayern Munich will be Bundesliga champions. Leverkusen will be far behind in the title race this season. I can't see any reason to think that this team is strong this season. Also, I don't trust ten Hag. It is very unlikely that he will build Leverkusen into a title-winning team. Maybe we will see some stable performance from Leverkusen, but I don't think we will see title-winning performance from Leverkusen this season.
When it comes to Bundesliga it is very possible that Bayern Munich can win because they are the defending champions and they might still have that heat in them but we should also not forget the fact there other clubs and Leverkusen is doing some improvement and that might be very challenging because Dortmund seems to been doing well to because they won there last match.
Ten Hag is not to be trusted actually because is last experience with Manchester United was not a good one and that is why everyone is skeptical so until the game starts then we are going to know if is capable or not because even when Kompany became the coach people did not have faith in him until he proved him self worthy of that position so maybe ten Hag will do the same thing but if he fails then we are going to know that it was actually the fault of ten Hag for Manchester United to be the way they are currently.