Really neat idea. I would love to know how you did it. Are they actually ui elements? Or are they just game elements that look like ui elements?
As for the core gameplay loop, it unfortunately was not very engaging. And I found the throwing mechanic exceedingly unwieldy and cumbersome.
I think this idea might almost be better suited to some kind of puzzle game. Check out the game "Void Stranger", and the creative ways it finds to let you interact with UI.