That looks good! I actually started with the "hanging shelf" configuration before switching to the rails.
I was really hoping I could figure out a way to mount the shelves with some sort of vertical supports that would simply wedge in between the rungs on my ladder. That would be a super-quick no-bolt installation. But I decided it would be a lot of work to build the supports and bend them to the perfect angle so that they would wedge into the ladder properly. Jeff Scherb posted a picture of a table that attaches to the rear wheel - I was thinking a modified version of those components might work with my ladder.