Hmm - very interesting. I like the comparison and I think it stands up well. Though I would classify Fry and Roslin as more moral than Riddick or Cain.
All of the above are willing to compromise their morality or out outright amorally in order to achieve their goals. In the case of Pitch Black the primary goal for which the characters are willing to become amoral is personal survival, mitigated by Fry's slightly more moral stance that if they can save the rest, they should.
In the case of BSG, Roslin is focused on the survival of the human race and will do anything to ensure that goal. Cain is focused on hurting the Cylon and will do anything to ensure that goal. The reason I would classify Roslin as more moral in this instance is that while destroying the enemy is just another (and ultimately more effective) way of protecting the species, Cain had no interest in that outcome and ultimately wouldn't have succeeded because, well, she had one Battlestar and that's it. So, reducing the situation down to survival as the ultimate baseline, Roslin was behaving more morally than Cain. Which is not to say either is inherently better than the other; it just shows that in this instance, Roslin was taking the long view.
An interesting comparison would be Roslin's very amoral theft of the election in aid of her very moral goal of ensuring humanity stayed safe from the Cylon. Or the fact that Cain probably would have kept the fleet safer in some ways (if she hadn't ditched the civilians) even though their safety would have been secondary to the amount of damage she could inflict, in her mind.
Re: Kara and her many parents.
All of the above are willing to compromise their morality or out outright amorally in order to achieve their goals. In the case of Pitch Black the primary goal for which the characters are willing to become amoral is personal survival, mitigated by Fry's slightly more moral stance that if they can save the rest, they should.
In the case of BSG, Roslin is focused on the survival of the human race and will do anything to ensure that goal. Cain is focused on hurting the Cylon and will do anything to ensure that goal. The reason I would classify Roslin as more moral in this instance is that while destroying the enemy is just another (and ultimately more effective) way of protecting the species, Cain had no interest in that outcome and ultimately wouldn't have succeeded because, well, she had one Battlestar and that's it. So, reducing the situation down to survival as the ultimate baseline, Roslin was behaving more morally than Cain. Which is not to say either is inherently better than the other; it just shows that in this instance, Roslin was taking the long view.
An interesting comparison would be Roslin's very amoral theft of the election in aid of her very moral goal of ensuring humanity stayed safe from the Cylon. Or the fact that Cain probably would have kept the fleet safer in some ways (if she hadn't ditched the civilians) even though their safety would have been secondary to the amount of damage she could inflict, in her mind.
Aaah! Moral and ethical dilemmas! :)