Judith Baker Montano responded to my challenge piece very quickly with a wonderful long and detailed letter, including drawings! Mostly, she was very positive about it, but she also provided really helpful feedback about ways in which it could be improved. I spent some time this week adding a bit more detail, mostly shadows and a few highlights, to enhance the final piece.
Here's a detail of some of the shadows I added. I backed the final piece with #14 needlepoint canvas, so I could stitch through the holes and not have to disassemble the framing. I also used a curved needle for some of the final stitches.
So, here's the final piece. I'm very happy with it and it's been a very rewarding experience.