Thanks for the clarification. I think I have a somewhat clearer idea what you're getting at now, but the distinction you are attempting to draw between ethics and goal attainment still seems wrongheaded to me. As the designer of a posthuman society, your ethics determine your goals; I don't see how the two are supposed to come into conflict in the way you suggest. (Maybe the demands of evolution will place constraints on the psychologies of feasible post-humans, but that's a rather different point.)

Nitpick:

An individual human can reason about it, and choose a different valuation; but they're then trying to act in a way inconsistent with their psychology

As it's currently stated, I don't think this claim makes any sense. If they can do it, then it's consistent with their psychology.