Jeanine,
What a handsome couple, she is very delicate and petite and he is tall and handsome. One little thing, in your underpainting check the corners of her mouth. They seem to turn down a bit more than in the photo. I have a habit of doing this and have to constantly check for the proper angle of the lips. I use a mirror and look at it over my shoulder and can usually pick it up.
It will be a fun one to paint.
Alicia