I liked the Unfettered organization and I’ll be sure to vote for it.
I’m not sure I agree with Sean in his dislike for the group because there aren’t supposed to be a lot of Unfettered; of course if they are supposed to be so rare why bother to give them write-up in the newest Bestiary?
If you encountered one it would have to be a wholly unique creature crafted for that particular encounter.
Even if they are rare they could have been around for a thousand years, or even longer. So if only one was created accidently every year, and only half of them joined the group you could easily have 200 running, crawling, flying, and burrowing around.