Very cool!

I'm looking forward to looking at your code. I tried to follow your conventions and style as
much as I could. While I'm an experienced coder, I am NOT an experienced Python coder,
and often make things unpythonic (and also harder than necessary) :)

I did PM you when I started working on this, but I'll drop you another one. I'm more than
happy to pitch in on whatever you're not focusing on. I did the armature and pose stuff for
a practical reason - I needed it for a project I'm working on. I won't at all be upset if I can
throw it all out now. :)

It boggles my mind that there's still no good way to transfer poses from DAZ to Blender (if
you know of one, please share - BVH is the best I've found, but it screws up some of the
bones)

I'm especially interested in looking at your bone orientation code. I found that trying
change the bone roll caused problems with constraints and setting bone transformations
from pose data. Been trying to figure out if this is a coordinate system problem, object vs.
pose vs. world space issue or what. I ended up leaving all bones at 0° roll.