I don't usually write reviews. It's also taken me 12 books in, to leave comments about this series. But here you go.
I have a deep appreciation for Hayden's King's Watch series. The writing is dense (That's a compliment!). He gives equal attention to character and to action. The very slow progression, the intrigue, the interweaving of story-lines and character arcs within each novel and across the series...!
There's a bit of frivolity. A bit of love/romance. I love both of those!
Start from the base of British mythology with a dash of Indian, add the Fae, Gnomes, Dwarves, magic-users of several varieties, two-skin, and more. With all of this magic and mystery, a thing I like immensely is that the heroes and heroines are NOT saving the world. They're fighting to defend their own backyard, to protect their friends and country.
There's a bit more smoking than I'd like, but hey, it's a distinctive character choice. And Hayden uses it well.
This is an incredibly well-developed world. Each new story-arc, each new exploration of species, merely adds to the sophisticated universe. All too often writers in this genre lose track of details and break rules that were established three books ago. I've not noticed that yet, and I'm on book 12. All the rest of my appreciation notwithstanding, this is the highest praise I can offer.