Edit: Went back and finished the game. Took 6 hours to beat it. Also did the optional boss (Reimu).
While there are some tuning issues as noted by other comments, I think the game's compelling. In some ways it feels more like a puzzle game than an RPG, albeit with more RNG than your typical puzzle game. Art, music and writing are all strong points as well.
The mid-late game actually felt way more forgiving and balanced than the early game. I beat all the Moriya bosses, as well as Reimu, on the first attempt. Final boss took 2 tries. The funny thing is that I forgot to heal Hina and she dropped dead on the first turn, so I beat him with just Nitori. Sidenote: Hina-spin absolutely wrecks multi-attackers. I enjoy this.
The only major pain point is having to scale the tower multiple times to open enough equipment chests to get sufficiently strong items to beat bosses. This involves forced encounters with the same enemies, which gets repetitive and makes the game take too long for a jam entry.
Bombs also didn't feel useful for the most part, but I suspect specific status ailments are particularly strong against specific bosses - I didn't end up experimenting with that.
Final note: How the heck do you catch that damn golden fish? Even with Miko's ribbon and the strongest armor, at 37 speed, I still can't get the first attack before it runs away. Maybe it comes down to luck.