Beautiful! Thanks for doing these things, really.
I feel like I should say something constructive, but the only thing I can think of at the moment is slightly deconstructive - Bigby doesn't have a beard in most published illustrations. Not that that's a problem; he could have grown a beard while he was in Sigil, or the statue might have been made by sculptors who've never seen Bigby. It might originally have been a sculpture of a different wizard, later identified with Bigby. It could be a different Bigby, perhaps an ancestor of the current one. Maybe he has a detachable beard that serves as his familiar (I imagine it makes a trilling noise when it's feeling stressed, and on those occasions Bigby tells it to "Calm down, Beardy, old girl."). And the picture's so small it might not depict a beard anyway. Hardly worth mentioning, but I feel like contributing something. So there you have it: the Bigby's Beard Issue, and suggested accompanying rationalizations.