This post contains SPOILERS for His Majesty's Dragon. Here's the non-spoiler post if you got here by mistake.
My minor quibble is about Longwings just refusing to have non-female handlers. It just seems too easy to me—a neat way to get women in the Corps without having to completely re-write larger British society. And while I'm all for having women in the Corps, even quietly, I don't really see anything about dragon breeds that would suggest a reason for that kind of partiality.
I have decided that the first Longwing handler's was female either by accident (only women were around when it hatched, a woman was the only one around that the Longwing liked) or by contrivance of the handler (in disguise, stole an egg, conspired with friends in the Corps). The first handler seized the opportunity and put it about as a peculiarity of the breed, and since then (1) only women have been presented to Longwings, so of course they've only bonded to women, and possibly (2) the dragon's been told in-shell that it must pick a woman. So it's theoretically possible that a Longwing could bond to a man, but they don't get the opportunity.
Yeah, okay, it's pretty contrived, but it makes me happy. Hush.
In alternate history news, I note that Nelson is not killed at Trafalgar. And a really nice piece of setup: a Japanese dragon drives away the armada of Kublai Khan, and in our world, the armada is scattered by a typhoon that came to be known as—the divine wind.