The title "Scarlet Trails" was one of my wife's many invaluable suggestions. I remember stopping her one day with the open-ended and seemingly impossible question: "What am I going to call this?" She had been reading some of the earliest drafts, and without a moment's hesitation answered, "Scarlet Trails." And then suggested titles for the sequels, each of which would have a thematic color as well--Verdant Horizons, Azure Wings, Amethyst Skies, Golden Reckonings, Umber Thrones, and Ashen Worlds.
I hadn't planned on a color theme. Sure...Cora's hair is a vibrant red--she prefers to call it scarlet--and there is a patrol of lawmen called the Crimson Guard. Other than that, the Company slays a reddish-hued dragon and the evil clandestine organization pulling political strings displays their presence in flowing red garb... So, it turns out there was a theme after all. And Heather had picked up on that.
While I can't say each volume will be as color-focused, I am now more aware of this possibility and just might look for ways to include the titular swatch in the text.