Fine arts
First of all, the arts are really wonderful, and the cutscenes are great so far.
Fair gaming mechanics
The gaming mechanics are fair but tainted by Gacha as you cannot proceed to end game content without spending lots of money to get the 5 stars characters AND weapons. Character and weapon pool are put together which makes you even harder to get what you want.
Poor performance
You can grind, but you better need to prepare few portable chargers with you since this game consume your battery in an insane rate and cause your phone heat as hell. I still do not understand how come a 2D game can have such consumption which can even match 3D game like Genshin or whatever open world games nowadays you can find in mobile game store.
Overall
You may need to reconsider to play this game as you need to invest lots of money into this game in order to enjoy it.