The basis of the world you're building is interesting, but the game is too barebones for now to have any real opinion. That said, here's a few things you might want to think on.
Characters tells you to go see some people but never guide you to where those people are. "Go see the counselor". Ok, where is the office? "Go see the counselor, his office is in the east wing" would be better.
When talking to the counselor the first time, make him say his name. When we're asked to go to Nan later, player have no clue who is Nan for now.
After being registered in the battle league, I had a bug when returning from the farm, it dropped me behind the school building in the front courtyard map. Had to no-clip to exit here.
I see the Big city have numerous districts. You should make each on its own map, and use your bus system to cap player progression, making the city map more digest and less bloated. Let's say, each school rep tier, you gain access to a new bus line, that can bring you to a new district. That way you also have the time to fine tune each district's map design between updates instead of having to work on all at once.
Current city map design is meh. Too big, too empty, too symetric. Look up some cities on Google Map and take inspiration from them, to have a more "organic" city map.
Haven't tested much the fights. Chose an Athlete, got the spear from the Guy in the classroom, unlocked the Target Practice in Zone skills by levelling, target practice doesn't work (stays gray in the battle menu).
I think that's all for now. It's mostly propositions of course, i'm not flaming you here. Mostly reporting what I think your focus should be for the next. I'll keep an eye on your game and I hope you'll keep working on it. Good Luck !