What a sweet husband! I feel as others have stated that a sewing machine is a personal item and I bet your wife would love to have some input of what kind you buy.
I have a Bernina 200 which also has the embroidery unit. I absolutely love my machine! The most important thing is to buy from a reputable dealer where she can get lessons in using it (most are free) and supplies (feet, bobbins, etc).
If I were you, I would give a card with a picture of a sewing machine inside and a note saying you are taking her shopping so she can pick out a new machine. She may like the embroidery unit, or maybe she would rather have all the bells and whistles for machine quilting. Let her decide. SHE WILL LOVE YOU FOR IT!!