The sannins are dropping like flies, Tsunade is the hokage and the only one left and Pain probably the strongest villain in the series at this point is about to go to the village, not to mention that Sasuke, Kishi's boy toy, has declared that he will kill the leaders of the village plus there is still Madara who wants his revenge against the Sengu and the only thing that was preventing him from getting it, Itachi, is gone and it just so happens that Tsunade is not only a Sengu but a direct descendant of the man who is the root of Madara's hatred but yeah its just a theory of yours right. Talk about stating the obvious, if Tsunade survives to the end of the series that'll be an even bigger surprise than Kakashi busting out MS.