I do not understand the logic of the original post. Why must EVERY scifi show or product have humor? Does one expect copious quantities of humor on The Shield, The Wire, The Walking Dead or any other drama out there? What I have a huge problem with is this idea that its a problem when a scifi show actually takes itself seriously and does not veer off into the realm of the goofy. BSG is a prime example. Its a show about the end of the world and humans being hunted to virtual extinction. The original series barely took that premise seriously and had them stopping at a casino shortly after the bulk of mankind had been exterminated. The new series does not make that mistake. Its suitably apocalyptic...as the basic premise demands.
As for Star Trek, there is no way you can say that DS9 and Voyager did not have humor (voyager not always intentionally). From Take me out to the Holosuite to Bride of Chaotica, there was plenty of humor in both shows.