Nicely done, I think it looks great and will serve you well. Curious, what's your measurement from the ground to the top of your stand?
I made my stand with a similar design but wasn't sure if I was going to stick with my location so set it on 1 1/2 cinder blocks. That height seems to work great considering that one of my hives is two mediums tall and the other is three. However, I'm afraid if I add too many supers, probably wishful thinking on my part, :), it's going to become to high to work comfortably pretty quick. I'm toying with the idea of removing the half of block, or maybe the whole block before it gets any further along.
Decisions, Decisions, Decisions! :?