Quilting is such a personal craft. What I may like or consider good, may make someone else go "Yuk!"
I like my front & back of quilts to talk to each other nicely. Having said that, there is no blue on the front, so if the corner of the quilt were to turn down showing the back and it was blue, it would be jarring to me. Of course, you could always applique some bluebirds or flowers or something, on the front and bring the blue to the top.
If you don't want to add the applique, I probably would go with a red and white print for the back, if you could find one that was similar to one of the reds on the front, or go with a solid red and quilt it with white thread. That would make the back a whole cloth quilt. Even if you use a panto, the effects are still stunning when the thread contrasts with a solid color backing.
Good job on the Dresdens. I have 360 of them made up for "Meet me in Paris" and just need to get the quilt put together. One of my many UFO's that I plan to address this summer while my husband is recovering from back surgery.