This is sixth in an Urban Fantasy series where plot and character elements span volumes. I recommend reading in order.
While you know what you're getting by now, this book acts as a good stopping point for the series. A lot of important arcs come to satisfactory conclusions by the end and are very well done, I'll say. So I'll have even less to say about this one than usual. The plot is fast, the events satisfying, and I was eagerly engaged for the entire story.
Even though this would be a good stopping point (and the author indicates it might be at the end), there are plenty of opportunities for an author as talented as Buroker to continue and I'd totally be down with that if she decided to go there. Val's family remains largely an enigma, and you can see that Freysha has some interesting depth to her. Not to mention that dragon politics are obviously convoluted and the whole "send a dragon delegation to 'legitimize' Earth government and bring it into the Celestial Courts" is almost as interesting a potential plot as "Earth as potential Celestial Tortuga".
So this is a solid five stars and I'm sad to see it (possibly) over, even though I'm completely satisfied with it as a whole.
A note about Steamy: One of the things that culminated satisfactorily is Zav and Val's relationship. Including a single explicit sex scene that puts this on the light end of my steam tolerance. I'm a little torn about this, even though it was very well-done. On the one hand, the series has been fairly chaste to this point, so the departure might jar some readers who came to count on that aspect of the series. On the other, it was about time and the power/intimacy dynamic between these two characters is important to their long-term viability as a relationship so seeing it play out, at least in part, was kind of important.