http://www.quilterscache.com/P/Pinwheel8Block.html

I am working on this pattern(Link below) and I am doing alternating white squares. My question is, what kind of quilting motif should I do that would make it look good, and sort of go? I am planning on hand quilting it. I would prefer it to be free.

Can you not mirror the outside edge of the pattern then infill with maybe a multi petalled flower to soften it...... :D