Pretty fun, honestly - rated. Please consider giving mine a play as well and rating.
Feedback:
I'd consider making everything ramp up a bit faster. I started getting a little bored before the first boss arrived. After that, things started getting interesting a little faster, as it got more challenging. But I'd worry some players might give up before that happens.
The way the power up screen appears is somehow a bit disorienting.
Some of the attacks have effects that feel confusing - I'm not sure if I just launched an attack or if I just got hit by something. A mix of sound effect and visuals causing that.