Thank you all. I had another "brain wave" at the time I was trying to stay awake after supper but kept falling asleep in my book. Since the black backing is marbled, I could use a gray colored thread. If I don't like the burgundy when I try it, I'll see about finding just the right shade of gray ... possibly a blue gray??? If I were to get exactly the right shade, it would bring out the blue in the melons, but not be overwhelming on the black.
Just a thought I had; it would mean buying more thread after all.