Absolutely, Lewandowski can kill most of the opponents in the league alone, and the most remarkable thing about him is that he basically never misses a match, neither enjured nor suspended - Bayern will then in return have a big problem if he picks up a (serious) injury missing 6-10 matches...
I hope they won't be like Barca-Messi relationship. What a disaster it would be if you need this particular player to keep winning. Any team should be able to score using nearly all of their players, that's what makes it interesting.
Even a keeper should be able to take a penalty at least.