If she's at all as cute as you make her out to be, then TONS of guys are checking her out EVERY SINGLE DAY. And more than a few are thinking about how to get in her panties.
Maybe it's BECAUSE things are good between you that she doesn't want to rock the boat? Don't look a gift horse in the mouth. Keep your marriage solid and happy, wanting her to be a hotwife is a nice-to-have, don't push it too hard.