If you do any stitching in the ditch, make sure you stitch right beside the seam on the side where the seam was not pressed. That way you are only going through 2 layers of fabric and the batting, not all the seam thicknesses. There are several advantages to not stitiching in the ditch...you can stay away from seams and the stitches show up better. I would stitch a design in the white rectangles just to have more quilting show up, even if it is just a row of diamonds or some other simple design. (I may be repeating someone else's advice. I didn't have time to read all the answers.) By the way, it is a very nice quilt. Good Job!!!