There currently are not many commands which check the stats of enemies, items, etc. You could throw that in the pot of suggestions for me to sort through. If you only want to check the block HP for a single block, then you could do that work with your own custom variables. But if you want to do this for multiple blocks would you need to have separate variables for each block and that could get tedious.
Honestly, I wouldn't recommend trying to make enemies work on moving platforms because it will likely produce undesirable results. But if you really wanted to experiment some more, you can make flying custom enemies by clicking the button in the top-left corner which says "type = land."
