This was a great ending to a great series, but the journey was much longer than the very shortly resolved ending.
Don't get me wrong, I loved the entire series. The characterization was amazing, the setting was pretty cool, and the plot was interesting. It just felt like a lot of action for a very short ending.
One thing Brown is a master of is the art of illusion. He'll have your focus centered on something only to completely switch everything up where you aren't looking. The main switch of Mustang's plan in the end was pretty genius, but at that point I felt like there were so many plans and switches throughout the whole series that it was just tiring and you stop trying to figure out what's going to happen next (which is one of my favorite parts of reading).
I'm excited for the next book to see how things go in their future.