Art: Loved it, it was clean, kept on theme and even had the cute little bubi and mousey. The only thing I could maybe critique was that some of the trash items clearly were made as much bigger pieces of art and then scaled down because they're a lot crisper and sharper around the edges compared to a lot of the softer landscape (This could have been intentional though and if it was, disregard!)
Music: When it all came together, it was nice and had a nice groove to it. I'll talk more about BPM and difficulty in a second.
Gameplay: Really confusing at the beginning. I realised quite quickly that I think I was just playing a static beat that sped up over difficulties but I think an non-experienced gamer might really struggle to pick up what the intended flow is. Not having any form of visual element to rely on at the beginning to get started made that a bit rough to ease into. I loved how you had an additional element of picking up the trash layered on top of the main flow. I usually found myself picking up trash to the beat!
Other: The interface is clean. I knew what everything meant and how to get where I wanted so kudos to that! I did notice that on nightmare mode, the background, player and trash kind of develop a mind of their own if you miss a beat and start sliding? I don't think that was intentional but given more time I'm sure that wouldn't have even been noticed.
Overall really good game and really enjoyed playing it once I got over the initial hurdle!