I'm very impressed with how good the pixel art is despite the relatively limited palette. The manual dithering/patterns/anti-aliasing/etc are very well done.
Sound effects are simple but very effective. The controls are easy to grasp. The characters are very cute, but sadly I gave up during the final "Nice" puzzle :d (which had a little wonky anatomy with the legs and feet, but i understand this stuff is VERY hard at a low resolution).