My opinion, but, Prince William looked great with the thick hair he once had...but now he just doesn't look good at all with the balding. I think if he shaved his head, or at least buzzed down to a zero, it would be a massive improvement to his appearance.
He's one of those guys who you can recognize as very attractive, but the problem is is that the balding is this eyesore, and makes him look sort of ridiculous next to his wife. That said, he will always look better than Harry, who looks like a jerk.
And I completely agree about his beard, he looks fantastic with facial hair. He could easily do the bald and bearded look.