If you enjoy The Expanse, definitely pick up The Mercy of Gods, also by James S A Corey. It, and the recent sequel (The Faith of Beasts) are some of the best sci-fi I've read in a long time.
Thanks for that. Dune used to be my favourite sci-fi, but, The Expanse maybe trumps that now. I'll definitely check these out once I finish The Long Earth :)