A shame. I've been waiting for this 'modular' design to kick in before I get too invested in 5e, but it's still just a phrase in an ad blurb. Considering how much material there is for Forgotten Realms, you'd think WotC would take advantage and crank out a few dozen class specializations stolen from previous editions and given a 5e paintjob. There's enough sects, guilds, organizations, secret teachers, and other such gimmicks to choke a shark throughout the published history of the Sword Coast.
Also, I'd bump this down to the 3rd worst kind of supplement, after the book loaded with 'unique characters' that was clearly made by handing an intern a stack of blank character sheets and the core rulebook.
Thank you for the review, hrm bummer they did not spend more time developing this book, something that would earn its place on the shelf with the other hard back books.