This is for the Jam version, haven't played post-Jam yet: Pretty solid, once I understood the main mechanics it went rather smoothly (except the frame rate, it dropped like concrete shoes in the Sanzu River when my duos of Slash characters just dished out worldwide scratches at the average speed of a shooting star - being super OP is fun, but I really need my PC to stay alive so an upper limit would be good, thanks).
Also did I mention that only 15% of the way through the game you just can't lose? On top of being already OP at this stage of the game, if you do lose a ship you can just rebuild it and you're good to go again.
Lacking challenge aside, it's pretty well made and promising at its core. The shipping mechanic + the team buffs, marvellous ideas! Also, you replicated one signature spell card for each and every enemy! As a Touhou player, that was super fan-servicey!