Are you sure you want to spend the time and money to make a quilt for someone you do not know and whose taste you do not know? Both my time and budget are limited and I cannot afford either to make a quilt for someone I do not know.
PWB has a great idea in a low volume one. One of the throw quilts in my living room is soft grey, taupe, yellow and cream.
If you really want to make a quilt for this couple, I suggest you learn a bit more about them, are they into sports, favourite teams, what are their hobbies? Favourite colours etc. Talk to the parents to get an idea.