I completed the 5 floors, at first it seemed too simple but I kept playing anyway, so it has something going for it.
I would consider the UX without walking under the UX elements (losing sight of the character), I understand the clock has to be collected early often when you are small and fast, but for 5s seems not much worth it.
The fps counter by default on is maybe unnecessary unless the game has perf. issues. I also wasn't sure what was the 100% going towards 300% for... or how the x1 streak worked... I seemed to have gotten 3 stars even with no combo
I wasn't sure if there was a difference between the characters besides visuals.
Overall it seems nicely done.