This is an absolutely amazing game! it didn't take long for me to start ignoring the crowd and just making music. I especially like how if you mix the same color twice you get a second layer of that instrument, but I wish the layers were actually separated. Example of what I mean: I don't particularly care for the default blue Gameboy arp, but I really like the second blue layer. So I put the blue pedal through lowpass and saved it to the loop pedal. Now I have the bottom layer of blue on mute. pass that into a mixer with the blue pedal and... the blue arp layer just comes back. I wish I could have had the solo without the bottom layer.
I think it would be really cool to have a ducker pedal that you can send things through, and when the crowd makes a request it'll have an asterisk to say that it needs to go through the ducker.
It would also be cool if there was some kind of LFO pedal that you can pass into the top of a highpass/lowpass filter but that probably makes it too complicated, and I don't know how that would work with the crowd requests. I also found myself wanting a chorus effect, but I don't know if it would make the game itself better.