Since the patterns on the fabric are mostly triangles, why not get some solids to match, make up one large block similar to one of the patterns in the fabric, and use this for the back? I hope that made sense! What I see is a solid-color quilt with one large block in a pattern similar to one on the back, with some of this fabric for the binding.
I wish I had a computer program, I'd show you what I meant. But I'm still a graph paper-and-pencil kinda gal.