It is true, Leverkusen is one of the lucky teams because they once broke Bayern Munchen dominance in the Bundesliga, with Xabi Alonso they wrote an unforgettable history, from Neverkusen to Neverlusen. Meanwhile, I guess the rich team you mean is none other than Dortmund, who like to sell their best players, as long as the price is expensive, they don't care even if they let them go to a rival team.
Next season, Bayern Munchen will most likely lead the trophy race again, and they are in first place in the list of favorite teams to win. Leverkusen and Dortmund may only be able to put pressure at the beginning of the season, other teams such as Leipzig, Stuttgart, Eintracht Frankfurt in my opinion cannot be relied on to stop Bayern Munchen progress. However, in the last two seasons I think the Bundesliga has become more interesting.
I want to see the power of dortmund in the bundesliga next season, they have not competed for the championship title for two seasons and that is a setback for them. Indeed, in the bundesliga the favorite team to be the champion is of course Bayern Munich but if they are not consistent then we will see another team that will be the champion.
Leverkusen seems to be having a hard time next season because they will find it difficult to repeat the success under Erik, Erik's performance in the premier league is not very good so his track record will certainly make him not confident in bringing Leverkusen to glory like what Xabi Alonso did.
But dortmund last season played quite well because they were in the middle of the season where their position was in the middle of the standings but in the second half season their performance improved and managed to close the season in the top 4.