Just a few final thoughts.
I had some severe ethical conflicts through this series cause, at some point, I couldn't help siding with life fibers: I personally hold no humanist nostalgia and Iong for our bilogical/physical condition and its limitations to be overcome by the means of technique (the very spirit of transhumanism), so I saw no problem with becoming and/or supporting the superior cloth-beings.
But then I realized that I was putting the cart before the horse: it is the mind and consciousness what I ultimately want to preserve and set free with the help of tools, not the other way around; it is our agency manifested in the will what constitutes the very line that separates the mind from its tools (including the body), and the reason why under no circumstances (and whatever form we take) we should never give up our responsibility and allow some god, machines or whatever to do everything for us, cause at that very moment we become essentially unnecessary and die as agencies (as it almost happened in Odyssey 2001, The End of Evangelion or, even worst, in Baudrillard's scenario of a world beyond sign and virtuality: a refound "material" unconscious state of "natural" brute machinery, constituted by mere elements ondulating perfectly but nonsensically, as with viral entities like life fibers).
So, in that sense, rejecting life fibers is pretty much like rejecting instrumentality, all for the sake of the self (or what we somehow understand as such).
Life fibers did seem a lot like the Kyubey culture (the analogy of humanity with cattle is clearly present) or, once again, like the sea of LCL: conscious or not, they are an all-as-one entity with no such thing as otherness within them; therefore, there can't be any sense of interpersonal conflict among them, thus no need for ethics, morals or even feelings as artificial systems to cope out with the minds' colliding.
However, the main problem is the tension between limits and freedom through an existence founded on difference. Since concepts like good and evil only have sense as choices we make while dealing with others, life fibers are neither good or bad but simply innocent. We, however, are not, and this series helped me remember that is preferable to remain like that (cause it entails a richer existence).