I hope this does not sound as if I'm picking on your wife, but it will to her, so don't read this one to her.
Your model needs to loosen up. The poses are fairly well balanced, but they are so well balanced that they are static. She could be a bit more animated, IMO.
Here's a little suggestion: Invite a close friend of hers to go with you all wherever you want to try again. Have the friend (the friend doesn't even have to know you) stand behind the camera position and talk to your model. Eventually your model will loosen up and start becoming more animated. You need to be ready with your camera, and always watch the light on your model. If you need to move, you move, don't ask your model to move if she is getting into it. The friend never has to get in front of the camera.