There's a lot of good, a fair amount of bad, and a moderate dose of ugly, here. The new options for Awakened characters/NPCs run the gamut from amusing to awesome, with lots of great new Traditions to change up the flavor of Mages/Mystic Adepts, lots of new Qualities and options to throw at Aspected Awakened, and the return of some Talent options I'd sorely missed (The Traveler is 5E's version of the Astral Adept, and tons of flavorful fun in my opinion; the Apprentice is able to access some Sorcery and some Conjuring, in a limited fashion, etc.), and some new options that are loads of fun (The Return of optional 'Old-School' Shamanism, the useful-but-restrictive variants on Buddhist, Romani, and others) and some fairly powerful, though none are to the point where they'll make metagamers and optimizers scoff at previous options. The Shadowtalk bits are some of the most humorous and ominous in any 5E product to date, and really impressed me. Also, for the long-suffering players/GMs who keep trying to make Alchemy a fun and feasible option for characters, there's many traditions/qualities/gear in this book that help it substantially.

Now, for the rough parts: Some of the mechanics are just not able to be used. The book included 'rules' for Focused Awakened which looks like tons of fun . . . but neglected to include the cost or other options for selecting them. There's also a ton of tantalizing new options for Blood Magic, some explicitly for players, but they're all locked behind the Sacrifice Metamagic, which is a bit of a tough sell as character development goes, and will likely still be a no-go for players in many games. Additionally, expect the (sadly) status-quo amount of grammatical/referential errors that are the new normal for CGL.

All in all, I love the book. The flavor, the options, all are great. I'd caveat that most of this content requires more GM/Player discussion beforehand before including in the game than most supplements, but almost all of the fiddly bits make for GREAT hooks and motivations intrinsically. Kudos to the creative minds behind a lot of these ideas.