The parsha presents the brachos of Moshe one by one to each sheivet -- "Yechi Reuvain...," "V'Zos l'Yehudah...," etc. Yet when it comes to sheivet Yisachar, rather than start a new pasuk with his bracha, instead the Torah tacks it on to the bracha of Zevulun, almost as an afterthought: "Smach Zevulun b'tzesecha v'Yisacha b'ohalaecha." The parsha then goes right back to Zevulun, "Amim har yikra'u..." Why doesn't Yisachar get his own spot in the sun, his own individual moment of attention? Furthermore, Chazal tell us that Zevulun and Yisachar made a partnership: Zevulun was a merchant who used his wealth to help support Yisachar, who dedicated himself to talmud Torah; together they shared the reward of talmud Torah. Shouldn't the focus be on Yisachar, who was doing the actual learning, and not on Zevulun, who just enabled Yisachar's talmud Torah? Why is the bracha directed at Zevulun as the primary recipient with Yisachar tacked on secondarily?
R' Chaim Kanievski in his Ta'ama d'Kra writes that the reason Zevulun is the focus of attention for this bracha and Yisachar is tacked on secondarily is precisely because Yisachar was the one who was totally immersed in talmud Torah. When one's life is Torah, one doesn't need an added bracha -- Torah itself is the biggest source of bracha a person can have.
Maybe that's what we are supposed to get out of Simchas Torah. The lulav is put away, we don't have to eat in the sukkah anymore, there is no particular mitzvas ha'yom -- so why do we have a Yom Tov? Perhaps the idea is that those items are just props, accoutrements, albeit very important and meaningful ones, but if one has Torah, then one can have simcha and bracha even if one has nothing else at all.