Very stylish art and UI and enjoyable gameplay but I think those early levels need to be much more forgiving to give new players a chance to get used to the movement mechanics. I saw you're already going to fix the menu highlighting but I was going to mention that too. The dialogue system has a lot of personality, I like the character reactions. With parts where the track can overlap other parts of track, the ground closer to the camera obscures the lower track that you're moving on so a transparency setting or being able to move the camera would be nice features.
Edit: Being able to select a character by clicking anywhere on the character not just the small circle would be a nice QoL feature. Also for the level / character select screen, as the levels are on the left, I selected that first but once you select a level, it starts right away so maybe a confirmation button for when you're happy with both options instead.