Neat idea, very chaotic
Not sure why pieces you drop lock in place for a couple seconds before dropping, it doesn't feel very good
I was able get a score of almost 2000 never using the "Solidify all blocks," throwing bits around haphazardly and just pressing the Expand All button whenever I was close to losing, which doesn't seem like the strategy you want people to be doing. (Maybe make it so blocks that are too low or offscreen don't get expanded?)
I like how the 3d fella looked, very soulful, you should do more stuff like that
You should probably add an extra button to go to the steam page to the post-game screen instead of just opening it in players' browsers