SGU could use some humour. Some of the funniest jokes in modern day sci-fi come from SG-1 and Atlantis, so why SGU lacks any kind of comedy at all is a mystery.
I don't think that it lacks comedy of any kind... it's just really toned down and different. The pilot had Eli throwing out some SG-style quips, but the big comedic moments have really come from brief scenes like the crew ragging on each other for smelling badly or Grier's prank with the space potato.
None of those were funny. Where are the moments like in 200 when Invisible O'Neill stuck his dog in the driver seat of his car? Or Teal'c's Jaffa joke from Seth? Childhood's End when McKay is trying to argue that forced relocation of a society is okay if it provides a ZPM? Doctors Coombs and Felger making cracks about Star Trek's technobabble in The Other Guys? Teal'c misuderstanding why a hippy would want to go to Canada in 1969? Sheppard ignoring McKay and Zelenka so that he could stare at girls in No Man's Land? Hermiod getting impatient with McKay in Intruder? Ronon scaring the shit out of the scientist in Critical Mass?
Except for Childhood's End none of those examples came from the first season of either of the last two series let alone the first 10 eps. Actually I thought Eli's exchange with Rush and O'Neill in the opening of the pilot was pretty funny.