I think you would be happier with the finished product if you quilted it. And, as you said, that will make a nice winter project. When I first look at the quilt, the red colors seem to pop out, so I would be inclined to go with that. (IMHO) You might lay several different colors next to the quilt and see what you think. I also agree that you should use a think dark inside border to give the eyes a place to rest. Whatever you do, I am sure it will be beautiful when finished. Be sure to show us pictures when finished.