Making the same decision twice... or thrice?

Sometimes it's MUCH easier to piece together a quilt backing from random scraps, bits and pieces left behind, rather than try and find that PERFECT backing. For example, I have a quilt that I pieced, oh I don't know, about 5 or 6 years ago:

From a pattern in a Judy Hopkins book, Big 'n' Easy: Super Sized Quilts for Queen Beds

and it took me another 3-4 years and at least 2 false-start purchases to find what I believe to be just the right backing:

tents, by Brandon Mably (available at The Quilter's Studio)

Now that THAT'S off my chest (but still on the shelf!!), I'm going through something a little different. Thank goodness for deadlines! I finally got all of my Friends + Fabric blocks pieced into a stunning quilt top. Just under the wire for the Sisters Outdoor Quilt Show submission.

However I now need to figure out what to use as the backing... within the next day and a half!
HELP!!!

My first gut feeling:

an Anna Maria Horner print... lovely color match and complimentary motif, but generally a bit more purple than I prefer...

My first fabric purchase:

a PERFECT compliment with all the right colors and energy, by Terrie Mangat for Free Spirit, but I'm wondering if it's just a bit too busy?

Some Kaffe Fassett shot cotton possibilities (because the quilt top is so darn busy already, and I do love how those guys quilt up):
within comfort zone for Linda:

and then...
not so much one of my go-to colors, but ruled the WOW factor next to the quilt top, don't you think?

Will I regret going with the Wow, but using a basically solid fabric in a color that doesn't exist anywhere in my world?? I welcome any input, but the prewashing must begin by this Thursday...