I piece mine most of the time now. Sometimes the back has some of the fabrics from the front, sometimes not. I usually start with a large rectangle of fabric, the width of the fabric, like 60x40, then extend all sides with 10" strips and squares (cut to 10.5 inches). I sit down with a tablet and graph it out. Easy to do in even increments of 10". I start with a rectangle because my quilts are rectangular, not square.
Joyce