Feels a bit odd to have a reverse elemental triangle, but meh.
The fact that you need 5 star fragments can be easily missed and you can't return to previous areas. Would be nice to have a save option before points of no return.
Some of the items just didn't seem very useful to me beyond the area that you get them in.
The MP drains are really annoying. Fortunately, you do recover MP.
There is at least one spot (celestial area) that has wrong passability.
Definitely appreciate having tutorial items.
Not a huge fan of how you need to use a key item to change costumes instead of being able to just change them via the equipment menu.
In the mountain? path area, one of the mountain corners is missing a tile when the other corners have it.
Your characters being on the map is neat, but feels a bit odd that they are running ahead of you, scattered, but somehow manage to quickly group together for a battle... then immediately are scattered again.
That hydra multiattack is really strong, but instant? (Isn't affected by paralyze). Killed one of my party members so I had to spend some time recovering.
The secret boss didn't give me anything except a bunch of reputation? (Which doesn't seem to be used for anything?) It had a lot of HP, but relatively unthreatening if you have fought all the enemies up to that point. It was annoying, but not hard.
A lot of skills seemed just mostly useless. Paralyze doesn't really do enough to waste a turn on, silence doesn't work on bosses and I assume neither does the one that prevents skills (though the ignite or w/e does). Not sure if there is much point in bosses not gaining MP when MP isn't used for enemies in RPGM without a lot of work. Oddly, curse works on bosses.
The hit all skills each character gets seem like they hurt the party more than they hurt the enemy. Makes them really bad to use.
Some enemies really aren't clear what element they are until they use an elemental skill.
The final boss was... ummm... easy.
Not sure what made you immune to the effects though.