Tomorrow Leverkusen are hosting Stuttgart. Leverkusen still have an insane unbeaten streak like 45 games you know. 
They have already announced their Bundesliga championship. However I don't think they would be complacent anyway. Xabi Alonso seems like he wants to maintain this streak as long as possible.
On the other hand Stuttgart are trying to secure their Champions League spot. They are actually 6 points away from the fifth position but there is nothing guaranteed while there are four more weeks. After that Werder Bremen loss I expect them to play better this time. I wouldn't bet on Stuttgart's double chance though but both teams to score looks quite nice @1.58.
From my predictions, in the upcoming match, Bayer Leverkusen will easily beat VfB Stuttgart and the reason I say this is that in every meeting between these two clubs, when Leverkusen competes as host, they can always get a winning score because it's all like you said if Xabi Alonso wants to achieve a new record with Leverkusen of one season without defeat. They have already announced their Bundesliga championship. However I don't think they would be complacent anyway. Xabi Alonso seems like he wants to maintain this streak as long as possible.On the other hand Stuttgart are trying to secure their Champions League spot. They are actually 6 points away from the fifth position but there is nothing guaranteed while there are four more weeks. After that Werder Bremen loss I expect them to play better this time. I wouldn't bet on Stuttgart's double chance though but both teams to score looks quite nice @1.58.
Betting on both clubs scoring is indeed a very good betting option but in my opinion the odds are too small and in my opinion it would be better to take a bigger risk betting on line -1 with odds @2.17
Let's see, I'm sure Leverkusen will score at least 3 scores in that match and Stuttgart will only score 1 score.