Definitely a very unique concept and a very very fun game., This is going on the replay list because I just got sucked in playing a bunch. I seriously need to know how you come up with these ideas.
Anyway though, gameplay wise. The one thing I will say is I'm not entirely sure if anyone of the enemies are special. Besides health bars. and different attacks. For example it seemed like the floating.. crane (?) had the ability to destroy blocks. But I'm not entirely sure if I'm right on that.
One other thing I would say is it seems like the ability to use a side of the blocks while they're falling still deletes the blocks when they land. Which is a little bit weird, but not. I'm not sure if that's completely intended. I feel like having it use from both sides could be a little more helpful. But it's also just a really cool mechanic in general to use whatever side is facing forward as the side that you're pulling from so not sure if it would help or not.