Thanks for the feedback! Stuff like the keycard is unfortunately a bug, as it is in fact meant to light up when the fight ends - but due to last-minute lighting issues, it doesn't. Hi-Fi Rush was a huge inspiration for how the game plays, that and Metal: Hellsinger, so it's good to hear that intent made it through!
The SMG is another thing that sort of fell flatter than the intention - it helped round out the sandbox, but doesn't quite mesh, so it's likely gonna switch to being a burst weapon in a future version of this project. I like the idea with the beat UI count - it was mostly there to help people keep time with another visual, but it could double as something like that in a future build.
Thank you for playing, and I'm glad you had fun with it! That bow on princess was a detail I added last minute and I'm really glad I did now haha.