Very fun physics, and I enjoyed the variety in gameplay, despite the simple mechanics. I think some of the later levels go on for too long, which was enjoyable in a stressful way, but if I hadn't lucked out and had a full bar at one certain point, I probably wouldn't have completed the last level.
I think the character looks fine, but the filtering is a lot, especially with the tiles. I think that having a I think the scaling camera is a cause of this issue, and I understand why it's there, but maybe having the camera "stick" between x1 and x4 zoom, and having it never be a sub-pixel value may help?