Yea, I agree the most recent episode is more "dismal" than the previous BSG episodes, which by and large are rather dark in terms of production and story. Of course, this is intentional given the turn of events revealed in episode 10.
Part of the allure the show has had for me is it's realism given the premise and plotline. Although it is sci fi and raises the bar in terms of production for the genre, it is a character driven series and I like the realistic portrayal of people in extreme circumstances. The issues of identity, morality and ethics mixed with the basic struggle to survive are done rather well IMO.
It does seem to me however that amidst the darkness and despair inherent in the plot, the finer aspects of human nature are always present and if they aren't overtly triumphant, they refuse to be suppressed.
PS Farscape was another series I enjoyed but I was kinda disappointed with the series wrap up feature.