Oh, my vote for the most smug would be the Tollans, hands down.
The Tok'ra can be arrogant, but at least they've been out there, fighting the goa'ulds, for 2,000 years. What have the Tollans been doing? Hiding! Making nice with the goa'ulds, covering their butts, hiding their heads in the ground! And all the while, saying "nyah nyah nyah you can't play with any of our toys 'cause we're better than you".
BAH! My hope is that sometime before the end of the series the Goa'ulds come and swat their smug little behinds and they have to come crawling to the Tauri for salvation. Jack'll spit in their faces.