ELLEN?!
The flashbacks were nice, and it does seem that the five can resurrect. It makes me wonder if resurrection technologies were being developed, and later after going to the Colonials whoever became the "original programmer" turned the Colonial Cylons into a pet project. Perhaps trying to fix the perceived flaws of both humans and Cylons? It also begs the question if the Earth Cylons were monotheists.
I'm thinking however that the head beings, Kara, etc. are some sort of force that ensures that the cycle occurs. The manipulations of Baltar and six being used to ensure that not everything went according to the "Plan."
It does make me wonder why Three didn't comment that, "Something wanted us to come here, something wants us to survive. I'm not wanting to end it out of being tired of life, I want this to end to be free."
Then again, the rest of the season being the fleet succumbing to nihilism and intentionally trying to destroy all traces of humanity and Cylon...ity might be too grimdark for even BSG.