I'm not sure I would call "The Martian Chronicles" a "franchise". It's a classic book that was made into a miniseries which my sense of nostalgia tells me was decent. (I bought it on DVD a while ago but haven't watched it yet.)
And the problem with referring to BSG as a "franchise" is that it means you have to include the 1970s series and Galactica 1980. *shudder*
I'd define a "franchise" as any related group of shows which are set in the same universe and. They have to be related by being spinoffs and they may share characters, or may not. (So Doctor Who, by virtue of the existence of K9 & Company, Torchwood and The Sarah Jane Adventures, would be a franchise. Trek and Stargate would obviously fit, as well.)
I'm not sure where V fits. If they would just make the bloody Next Generation miniseries they promised ages ago...
I'm also not sure how I'd rank them all, but I'd definitely have Trek at the top of my list. I might put Doctor Who next, then Buffy/Angel.