Of course! Simply put: so much disappointment. He was so sure that these people had to be the most interesting humans on Earth in some way or another, and then Halcyon turns out to be this super dull guy with lots of morals and integrity who doesn't really want anything but to live peacefully. It's not that Puck thinks those are bad things to strive for, per se, but he doesn't want to waste his time hanging around someone like that. You'd think that the lovely Mrs Renard would be a little more fun, but nooo. Puck is nothing but happy to have gotten away from those two.
Fox, on the other hand, must have somehow inherited all the recessive fun genes. She's one of the most interesting mortals Puck has ever met, although she doesn't quite measure up to Xanatos in his eyes - mostly because, while Fox likes doing things for the challenge, her ambitions aren't nearly as high and fantastical as those of Xanatos, and she doesn't quite have that very fascinating Xanatosian way of taking everything in stride that so very much sets the guy apart from other humans. She's definitely on Puck's top five favourite people list, though.