I just finished a SBS quilt for a friend of mine. Her Grandma hand appliqued 30, 12 inch SBS blocks about 40 years ago, and my friend found them in a closet in her Mom's home. I used 30's repo fabric as the sashing, backing and binding, and it is just a gorgeous, gorgeous quilt. But, I did think it would have been more interesting visually if the SBS's had been facing in different directions. By the way, your mock up is wonderful!! Might have to use that idea if you don't mind.