Oooo Star :D:D:D Those are pretty blocks :D:D:D
I like the idea of the S curve too... with all of the darker blocks, you could make the S very open and it would take your eye all over the quilt :D:D:D
I found it easier to keep my blocks contained within the allotted area by measuring and counting my blocks, figuring out how many wide X tall I could go, and then I used masking tape to stay within that boundary while I was laying them out.