When I was breed shopping, I wanted a smart dog. Papillon was my first pick. Cute, small.. blah blah... I ended up with a Corgi. I think he is #11 on the list for smarts. Cute.. smallish..
That said,I think a "smarter" dog might be more of a challenge.. You cannot trick them into thinking you have treats for them if you are just trying to catch them. They will chase anything that moves.
If I ever go breed shopping again, I might start at the bottom of the list. hehe.