Cute logic. I do feel like all the unused blocks make the level feel a little bloated, but I guess finding the correct blocks to use is sort of part of the challenge. Not my favorite, but not bad.
I find the solution to this level incredibly odd, so for me at least, it really gives something to think about.
Edit: Why is it that there are 2 solutions and I couldn't find either of them for the longest time?
Got 2-offed first attempt. Was a little more careful next time and got it. :) Pretty straightforward on the whole, with a couple opportunities to mess up.