I could have put it out on Smashwords, which is a publisher I respect. I have three novels on that publishing platform. An advantage of Smashwords is they try to help authors get their work in correct shape by giving feedback. I have found Smashwords to be more helpful than Amazon in that regard. Technically well-written books can reach premium status that qualify them for listing with other sellers.
I could submit it to Avignon Press, the small publisher who published the paperback version of Heartland. Avignon Press offers very good editing services. Unlike Amazon and Smashwords, publication is not guaranteed. If Avigon Press accepts a book that means at least one person besides the author thinks the work is good and is willing to put time and effort into publication. Since there is a tsunami of new books coming at readers each year, and there is not an “Angie’s List” that separates the well-written from the well-intentioned, I prefer to publish through publishers who share my interest in selling books.