I like that this really feels like a complete game, rather than a jam. It's impressive to see this from a 1 person team.
My only concern was the pacing of the game. The campaign felt like it progressed a bit too slow, and the Arcade feels like difficulty doesn't increase long enough. After the first both in Arcade, I stopped because it felt like it took forever.
On the good side, the campaign is very well done, the story makes sense, and they justify the core mechanic. They also give mini-goals which gives more purpose to the game!
The mechanic is actually nicer than I initially thought, because it allows for a break in the Bullet Hell gameplay, but also reverses it completely, trying to get as many as possible.
I liked you could add a bit of dynamism to the music and also the background, which added more diversity to the game.
Well done!