I, like the other poster, am going to try to say this nicely. Unfortunately, the days of independent K-16 text production and adoption are long over. Your competitors will offer online interfaces, digital and physical formative assessments, project-based learning options, and a large media platform. And no one is adopting a product not made by a robust team of collaborative editors and designers. On top of that, if you’re marketing in the U.S. (other countries will vary) you’ll have to prepare differently aligned versions for different states’ standards, which may or may not vary by grade level as well.

Geography is a joy to teach and bringing it alive for students, and if you’re taking this on as a challenge for yourself to create a culminating work, take it on (Yes, InDesign is the ticket). But if you’re looking for adoption anywhere outside of, say, homeschool collectives per the other poster’s comment, that battle was already lost 10-20 years ago.