A preferred phone number option would be great. Many times parents do not list a home # and then we do not know what number to publish as the student's "home" number. We have to choose to add one of the parent's cell #s to the students contact card as a home #.
What our admissions director has done is on the application for home phone field on the student, he has made it mandatory and that way a parent has to enter a phone before being able to move on. That way the parent decides which cell # to put as the "home" number for student contact card.