When she asked for a quilt made from predominantly jewel tones, I knew just what kind of fabric I wanted for the backing,
I made two "Rules" quilts for myself. Here's the Black one,
I found a terrific Jane Sassaman fabric for the back, which I loved so much that when I pieced it to make it big enough for the backing, I matched the pattern so the seam would be invisible.
At a talk I gave a while back, a fellow quilter said to me, "You like busy backs." I don't think of them as "busy," but I think a big plain backing, which is what you get if you use a small print, looks very dull and uninteresting. When I was drawing, it was important to frame the drawing so it showed the drawing off well. To me, the backing and the binding of a quilt do the same thing. They need to relate to the quilt. They need to show you're not "asleep at the post." Like Chris says, "Don't drop the ball on the back."