Granted, my view of Weir was definitely influenced by a fic I read, though I can't for the life of me remember the title or the author. I just remember that Kavanaugh's hair was dyed blue (or was it that his pony tail was cut off?) and Weir called the boys in to see if they knew what happened. John successfully lied about his and Rodney's knowledge of the events leading up to Kavanaugh's hair massacre.
It might be a different fic, but there's one where the author wrote about how it's not really "John Sheppard" and "Rodney McKay" anymore. It was more "JOHNRODNEY", because that's what Weir yelled when a prank was pulled.
Ronon's the little brother John and Rodney are teaching to follow into their mischievous making footsteps. Carson is the long-suffering brother who has to deal with the aftermath, and Zelenka's their inside-man who occasionally helps out.
So. That's my Atlantis.