Music and general sounds really would have helped making the game feel more alive and is that which I feel like is missing most.
Other then that, this is a generic platformer which has no feature you could call unique (everything is just visual). This is fine as there was a limited time and it's already great to have anything playable! But it leaves the gameplay being stale.
I think the part I like the most is the art. It is nothing revolutionary but fits what the game tries to achieve and I could see it being used in a more refined game!