It's been a long time since I dipped into the epic fantasy genre (I burned out on the meanderings of the Song of Ice and Fire after A Feast for Crows, and don't think I've been back since).
There is a lot to like about this book. It is epic, and it is fantasy, and the world-building is both rich and not beholden to the standard tropes of medieval (or even early modern/17th century-esque as this seems to be) societies. It's a world that doesn't have the typical misogyny or homophobia by which some authors announce the authenticity of their settings, and is better for it. Nothing about such things really adds realism to a setting, while realistic relationships between people certainly does.
The point of view characters are for the most part sympathetic and sometimes noble, though sometimes a little too much so.
While I welcome the overall positive tone, I think the balance has been missed, and it's here that we also see some of the real weaknesses in the story. Shannon has built a very rich world, but while some fantasy authors would trap you in it for seven books and force you to wallow in every tiny detail that they've invented, Shannon spends several hundred pages setting out the basic ideas of the world and beginning a number of threads of narrative, but then is in such a rush to tie them off in a single volume that she hops, skips, and jumps across geography and plot to get the job done. A wealth of mythology and background is dealt with in sudden exposition dumps to get characters up to speed and quests done without having to work for them.
Normally I'm wishing the author would stop dragging things out for eight books, here I was wishing she'd taken some time to break this into three, and develop the plot a little more. There are so many quests to get through and so little time to do so (because it's a standalone book), there is no real sense of risk or jeopardy in them. Things go really well most of the time, and the supposed injuries or danger never feel real - it all ends up feeling a little like a beautifully written (and it is beautifully written) Saturday morning cartoon for grown ups. The world feels deeper, but we're not given time to really take it in and appreciate it, despite how thick the thing is!
I won't get into the international politicking for the sake of avoiding spoilers, but this is again somewhere that could have had richness of narrative, but doubles down on the lightness.
All in all, Shannon's imagination and writing skills are on display, and to be admired, but the book is much less affecting and involving than it could or should be, I feel. Lightness like this for three or four hundred pages would be great, and I'd probably chew through a series of it. Eight hundred pages of it leaves things unsatisfying, and not terribly interested in returning to the world (there are other books set there, but not I think continuing this story).