Ah, but I think William is a genuinely good bloke, so perhaps they are just being honest about this. Perhaps there aren't that many negative qualities about him to talk about?
Of course he has flaws - everyone does! He's a human being just like the rest of us! But William's gift is that he understands what he needs to do
and he knows how to conduct himself in public - we don't see any temper tantrums or throwing of the toys out of the pram, or whining about this that or the other to anyone who will listen (IMO he's unlikely to be like that in private either).
He understands he was born into great privilege and wealth, and has a duty to this country and its people. He understands that he is there to serve and represent us. He
listens to people.
With his Queen and their children at his side, I believe he will be a fabulous King, as does my cat