I would strongly discourage skipping CB. There is one major plot thread that concludes, and another one that starts being set up:
Investigator!Miller finding out more about what attacked the Ring Builders, his (apparently final) death, and our first look at the Bullet--although it takes a couple books before that one starts to pay off.
CB is very different. I personally enjoyed it, especially the bits where we see how the Roci crew has grown since the start (in that we actually start to feel out their characters more), but it's definitely got some flaws. Combine that with the change in scope and focus, and it's easy to see why Cibola Burn is one of the less popular books.
Nemesis Games is fantastic.