Still hopeful the MC(Tsunade) is a munchkin and uses fore/meta-knowledge, as well as practices(then Masters) as much as possible. All the various elements, even those she is not pre-disposed to. So she should master all 5 elements, then start working on their combinations, so she can mimic the kekkei-Genkai. Like Wood-Release. Maybe using whatever she remembers of "modern" medicine and biology to radically improve her iryohutsu. Maybe to the level of healing anything, regrowing limbs, maybe even making herself biologically immortal, which is something she SHOULD be able to do eventually. Mastering fuinjutsu, not just because it is an Uzumaki specialty, but because it is borderline magic. Basically doing all the amazing things they did with scrolls on the show, even borrowing from other fictions and stuff. Like, Harry Potter Runes and Enchantments, expanded spaces, charms, traveling tents/trunks(the kind you can live in), enlarging and shrinking, etc... Things like Structural Analysis from FATE. Even possible methods of making money later on, writing books/stories, investing in things that could be successful, like introducing underwear that is attractive, and offers support, simple things in modern society that do not exist yet she could corner the market on. She knows there are people in this world who can read minds, maybe look into methods of organizing and securing her own? Occlumency, Mind Palaces, or something? Maybe even figure out a way to heal Mito before(and after) she passes on the Tailed Beast, so she does not die?
It is unlikely, but maybe even eventually, when this story(in this world) has run it's course, she could even figure out a method to travel, turning this into a kind of multi-cross. Having her continue to improve her skill/abilities, while still gaining new ones. Harry Potter, Elder Scrolls, ASOIAF, BtVS, Star Wars, Stargate, DBZ, Fallout, Marvel/MCU, DC/DCEU, etc...