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!

I really liked the art. It would have been interesting, as mentioned in other comments, if the game could break in more ways—like corrupted platforms stopping working or controls not always responding.

That said, congratulations on managing to deliver something functional in just 3 days!!

The platformer controller felt good, but I wish there was some audio. Also all the "errors" were purely visual, would've been fun having something break in another way.