Wow, this is neat because I never realized the problem folks had with synthesis was a about the loss of individuality. Ie, I never saw the rewriting of the DNA as a thing that homogenizes all the creatures in the galaxy in any way, and the ending does not suggest this either.
What bothers me about the synthesis option is the assumption that the catalyst makes that rewriting the genetic structure of all life is necessary in the first place. There is no premise for this. The catalyst decided that all synthetic life would wipe out all organic life in the first cycle. Thus, it chose to use the reapers as a way to preserve the organic life and achievements of that cycle and make room for organics to try again. Every time it those new civilizations reached the point of creating synthetic life, the reapers returned to clean up the inevitable mess.
BUT...in my game, Shepard shows that it was possible for organic and synthetic life to cooperate. This is illustrated in the Rannoch stuff. Ie, the AI was incorrect in assuming mutual destruction was inevitable. My commander showed the cooperation was indeed possible.
So…I guess what I am saying is that the synthesis solution is not needed. And the catalyst’s assertions are not based in observation…BECAUSE it has continuously destroyed organic civilizations BEFORE any such peace or utter destruction could be achieved. Hence, it assumes all synthetics could wipe out organics, but has NEVER seen it happen. Hence, its assertions are based on nothing more than a projection from the first cycle. It has never given any subsequent cycle the chance to prove it wrong.
This cycle was different because Shepard delayed the reapers. And a peace between geth and quarians was achieved. To me, that was what made this cycle different...the simple fact that the reapers didn't get a chance to reap. The catalyst claims that organics are finally ready for the final stage of evolution. But I rebel against the idea that this must mean synthesis is an answer. They are a unique cycle because they got a dammed chance to be!
I do not see synthesis as necessary just because the catalyst says so. The game clearly shows that the organics and synthetics of this cycle can coexist. And that...to me, is a much cooler "utopia" than magically making them all hybrids. It is...I don't know...it cheapens the story for me. It is too easy. Like Legion said… “We make our own future.” What makes this cycle unique in any way is that it finally had time to achieve understanding between synthetics and organics because the reapers were unable to interfere. And the destroy option stops their interference forever.
The fact that peace could exist, that understanding could be obtained between synthetic and organic life does not support the catalyst's assertions. And its claim that "the peace will not last" is not based on observation. It has never observed any cycle to completion, and thus does not have any evidence to support this claim.
Sorry for the long post…I am not sure if I am making sense and may have went in circles a bit! 