I really, really loved this book, until the last 100-odd pages just went off the rails.
I had a couple of minor issues early on. While Sarene and Hrathen's chapters were slow and meticulous with things unfolding very slowly, Raoden's chapters were pretty fast-paced and almost episodic, and they ended up feeling shallow by comparison. The writing also wasn't always great and it took me out of the experience.
That said, I loved the overall worldbuilding, the characters were interesting and likable, and I thought the magic system and the intrigue surrounding it was stellar. I could only rarely predict where stuff was going, and I liked the pacing, the politics, the various character dynamics, I could go on.
Near the ending a lot of the story just fell apart for me. The pacing changed completely but rather than giving a sense of urgency it just felt rushed and sloppy to me. There were a few too many weird and unnecessary twists, conveniences or just straight up deus ex machinas. I can't really explain it without going into some pretty intense spoiler territory, I just really didn't enjoy it and it soured the entire book for me :( I considered giving it 3 stars but I just enjoyed the rest of it too much to let a bad ending bring me down as anyone who's heard me talk about Mass Effect 3 will tell you. It's a really great book with a really blah last fifth, and I'm incredibly excited to read more of Sanderson's books! :D