Really interesting. As somebody else commented, a snow/snowplow theme would have been really cool.
The main thing I would add is a difficulty curve. Right now, once you have the routine of moving up and down, it seems like you can play forever without dying. What if the shapes started spawning faster and faster, or different shapes with different colliders could spawn? Maybe spawning on different parts of the screen, so you have to keep running back and forth? Could even have some immovable blocks that act as obstacles, until you push explosives into them?
This is immediately a really fun game, with some extra polish and difficulty it could be great.