Good news and does this mean Bayern Munich will return to dominate the bundesliga again?
Yes, that's for sure, because Munich is the only team in the Bundesliga that's focused on the title. 
Looks like we are just waiting for Dortmund's efforts this time whether the club will return to be a challenger to Bayern Munich.
Don't expect too much from this team. Dortmund is a business club; they don't focus on trophies but rather on managing their players so they can be sold at a high price.Leverkusen? Finishing in the top four is already a good thing for them, especially considering Ten Hag career.
Dortmund can not be trusted when it comes to winning trophies or challenging Bayern Munich for the title for next season because they are not ready to win the trophy from the way they are focusing on business, they struggled last season in the league but they were focusing in the champions League no that they want to another season they are supposed to spend more on players but they will rather spend small amount to build and sell bask to other teams instead of using the players to fight for the trophies.
Ten Hag and Levekusen should focus on developing the team to a good squad if they end up having the opportunity to win the league ahead of Bayern Munich it's a good thing for them but the goal of the team should be winning a trophy not just finishing among the top4.