I agree with you about the smile, I think the pics would have worked better with one, even one that showed just at the corners of the mouth. I think if the model doesn't smile, she'll need to convey more with her eyes and I don't think this model is doing that. However, all that being said, she is an attractive woman and smile or not, they is obvious.
As far as the individual pictures are concerned, I like #1 the best, although I wish her head was turned a little more toward the camera. With #2: I like the theme of the shirt and tie, but the crop is too distracting. I also find the hand distracting. With #3: This one is also a good photograph. The only thing to keep in mind is the crease at her neck and shoulder. That should easily be fixed by moving her hair over or dropping her near shoulder.
As far as the lighting is concerned overall it seems good to me. On #3 the main light looks low causing the shadow from her nose to move into her eye.
I'm just starting out too so I hope you don't mind the observations. I don't have many examples to show myself so it's easy to critique from the benches.