It will not be easy for Leverkusen to defend the title even though Bayern Munich with its new coach next season will not necessarily perform well.
Bayern Munich is the team that dominated the Bundesliga before last season that dominance was broken by Leverkusen so of course there is greater energy from Bayern Munich to win the Bundesliga title again and apart from their new inexperienced coach I think their squad is very capable will help Kompany (Bayern Munich's new coach) adapt quickly and develop the team's performance.
And also several other Bundesliga teams are also starting to develop, so that will make the competition much fiercer.
I predict that next season the Bundesliga title competition will be contested by more than 2 teams, and that will make the Bundesliga much more competitive.
That's true because it's not easy to defend the title with the minimum quality of players and it's certain that last season's consistency will be different from next season. However, if you look at the quality of the coaches recruited by Bayern Munich, Leverkusen's opportunities are still quite open because the new Bayern Munich coach is not very experienced and proven. Kompany is still very new as a coach and there are still many things he may have to do to make the team more solid and unified.
That should be the case and there should even be three or four teams fighting for the title next season so that the Bundesliga will be even more exciting and tense. Compared to the previous few seasons, Bayern Munich was a team that always dominated and was difficult for other teams to beat.