It's difficult for Leverkusen because in the end there are only 2 options for the Bundesliga when it comes to trophies, one is Bayern and the other is hoping Bayern play very badly and other clubs can compete for the championship but for this season I doubt Bayern will play badly (like last season).
Bayer Leverkusen made a great start to the league. Their only point loss was a draw against Bayern Munich. Since that game was away, it can still be considered a great success. Boniface, who scored 7 goals in the league, along with Hofmann, Frimpong, Wirtz and Adli are terrorizing all teams. When you play so effectively on offense, things are easier.
Xabi Alonso wants to prove himself as a young coach and has made a very good start to his managerial career. Such young managers usually have a positive impact on teams. Bayer Leverkusen showed that they made the right choice.
I don't know how long they will stay at the top of the league, but they have already shown that they are a serious threat to Bayern München. This season the league looks like it will be more competitive and exciting.
The excitement and competition started when Leverkusen stayed unbeaten after five game, they kept climbing up the table without dropping a single point and Munich which used to be the fierce team in bundesliga was almost looking like they would have a tough time contending Leverkusen and it did happened when they drew Leverkusen at their home.
Most likely they may meet again at the finals although Munich is at the third position on the standing and I'm sure they will get better by mid season and get back to contend the top position with Leverkusen and may probably meet at the finals, I'm pessimistic Leverkusen may soon drop point probably with a draw by their next meeting with Wolfsburg as they will be playing away, although Wolfsburg may not seem like a strong team but they will want to share the points as they are home. Xabi should be considered a great coach if he is able to finish second, because he is very young a Coach and it's his first time at the bundesliga.