I had a pretty good time with this one, though I didn't make it past the defensive enemy before throwing in the towel. The chill vibes of the soundtrack are super well suited to the block-breaking and really put me in a zen zone.
The text was pretty hard to read, especially at fullscreen, though it was kind of irreverent and jokey anyway.
Gameplay-wise the addition of various spells powered up by various levels of collectibles was a good idea (though I never quite figured out what the ultimate level heart spell did - I feel like I launched missiles whenever there was a new ball?) and let the magical girl-ness of it really come to the fore in the gameplay as well as in the story. The character portrait art for the non-hamsters was also very nice.
The only thing with breakout/pong is that often aiming for that last brick or whatever is a huge pain in the ass. Also there was the occasional strange physics quirk with the ball that wouldn't bounce quite the way I was hoping...
Overall I would say everything came together really well here and I might honestly come back again. That defensive one is kind of rough though.