the main question to me: did the Colonials deserve their fate? We had long, sometimes heated and overall inconclusive discussions with DaruMozu and other people about this subject. I am still not convinced that creation of the cylons was so terrible act... But anyway, i would be happy to discuss it again if there are interested people.
When I first think, WHY is their creation terrible? Why would it be? I never understood that and I felt Adama had the most coherent view on that because he actually asked the question which meant, he did THINK to ask it. Whereas, Roslin didn't ask that, she just threw them out the airlock. More props to the symbolism in the show creation because, I think this version of BSG makes a contrast with procreation, and the concept that "parental guidance" or lack thereof cannot be ignored without consequence. Maybe it's because Adama had children and Roslin did not.
If you saw The Animatrix, the "Renaissance" episodes are obviously a big influence here. Where, the created machine is just a sentient being and then, it was abused and retaliated. The comparison you made to slavery is good. And how can we not then ask about Cavil's logic and "the centurion side of the family" and the fact that he still wants justice?
He doesn't accept the god, therefore, the justics is according to his own reasoning. If I had to make a statement, I would say it was immoral of him to frak with his "siblings" and indoctrinate them. He wasn't just a bitter hag to himself about what happened, he BECAME the "devil" figure, and I think that was hurriedly created in season 2 as a setup for the myth later. But still, to me, it represents how IF act according to your own morality, and not the morality of a larger group, it can have consequences if you are not "perfect".
I will suppose that being "perfect" is not at all what Tory spoke about - even though she was the one to pass the idea to Baltar!
For the sake of the mythos of the show, being "perfect" is what SD6 said it was - your life played in harmony with god's plan. Cavil was not in harmony, and wrought destruction. But did Baltar bring destruction as well? However un-planned in his conscious thought as opposed to Cavil?
I think there are 2 flawed creatures (I'm saying this to represent human and cylon for your "responsibility" question. Cavil and Baltar, for example. What is their difference? Baltar changed his mind. Cavil did not. This brings me way back to the concepts of the "fiery furnace of refinement" where the dross is burned off and you remove the IMPERFECTIONS. Then, you end up with a "perfect" thing. PURE.
Baltar went through that process and was "redeemed" literally and figuratively. I think on some level, the rebel cylons did as well, because they changed their minds. Repent = Change of Mind. So, some of the cylons survived and others did not.
I think this might addresss the "responsibility" issue. You have 2 peoples warring on each other, both could die. But both could also live. Or, one could overcome the other. Pieces of both survived, and they became one united thing. I like that the hybrid child was the major theme from the beginning, because it shows coherence. For as much sh!t as the creators get for their "failings" or whatever, at least they had the general concept worked out from beginning to end.