I thought of sashing and then having them be off set hard to explain in type but maybe making a 12" in to a 14 x 16 rectangale shape by adding a boarder around the block, then doing on the 12 1/2 size then a 10" and making it into a pizzle with sashing and boarder to break it up. Hard to image yeah wish I could print my ideas. sry if its no help.