I've thought a lot about the C&C I've gotten lately. I certainly appreciate guidance, and am trying to take advice to heart. I ordered some books on posing from Amazon, and am considering other avenues of study.
In the meantime, I decided to break-free of my poorly received flat lighting. I hope you all find these shots more compelling; I think I finally got the background at least at a different lighting/tone. I wound up using a small packing box as a barndoor to keep the mainlight from hitting the background; a "real" barndoor is on order, though the make-shift one seems to do okay.

I know I still have a lot to learn, but hopefully these are a step in the right direction.
So here they are: