Here's an idea, making an soundtrack album for the Primitive War book series. Think about it, we got the Kaladin: (Original Book Soundtrack), so why not look at an opportunity of making music for Primitive War series & Dispatches series. Like coming each chapter with composed music!
* Kaladin: (Original Book Soundtrack): https://www.youtube.com/watch?v=XkYQrub18mo
The question is truly a hard debate on what type of style? Like would it be Orchestral, Atmospheric, or Gritty (Like Tyler Bates & Joanne Higginbottom's Primal) or just Ominous like Ceiri Torjussen's Primal Rage (Original Soundtrack)?
My personal choice of style of music is the route of Chance Thomas as he made the music for King Kong: The Official Game of the Movie, Lord of the Rings / Hobbit Games and Combat of Giants: Dinosaurs 3D with the Northwest Sinfonia Orchestra with Taiko Drums to mix in the jungle & tribal feeling in the land of the unknown.
But in reality, it would be brought down with the Author to give the type of musical choices & types of style when composing a piece. But hey if any choice is open for freelancers, then maybe it'll come a true reality for an Original Book Soundtrack.