I love the look and mood of this game and the way the flower powerups work is pretty fun.
However I find the screen really crowded! My main problem is that the little gems disappear so fast, I put most of my attention into managing where on the screen I am, and not much on actually noticing the enemies' attack patterns. The boss fights are a little more interesting since I'm trying to maximise damage while avoiding getting hit, but I still end up sticking directly below and focus firing up 90% of the time.
Constantly being forced to miss pickups or get hit overextending doesn't feel very fun, and that's where most of the struggle is. I think maybe it'd be better if there were a little time/space for pickups to collect before they disappear (I'm aware if you stop shooting they attract, but they can still be a pain to actually collect), and if there were more thing on the field - like variant enemies or obstacles - worth paying attention to.
That being said, I'm not a big shmup fan so I guess it could just be a skill issue haha. Either way I loved the art and feel!