Some changes to men I understand and accept; after all, they're just rectifications--no cancer, no genetic pathologies, strength, control, dominion...scratch that last one, maybe. They are not alterations so much as completions of an ideal. But to alter oneself fundamentally is rather odd.
Let's make two assumptions for the moment. One: morality is simply an evolutionary tactic to increase the chance of one's genes surviving. Two: therefore, morality is uniquely designed for men, more or less as they stand now. It depends of human weakness and dependence on others, and has no intrinsic value, but receives value as a reproductive strategy.
Now, when we go to change ourselves, the question is, as Sheri Tepper succinctly put it, "What shall we become, now that we are no longer men?" And by what goals shall we be governed? What morality, if our morality is part and parcel with our form, shall we adopt when we leave that form behind? By what criteria shall we men judge these after-creatures, who are superior (I imagine) in mental and physical ways, perhaps immortal, perhaps near godly? Our morality cannot judge beyond itself; we have no guidelines for these super-men (yes, in the Nietzschean sense) who are beyond it. How can we then create them? Are we to be governed by necessity, or will-to-power, or aesthetics, for it cannot be morality. We have left all that behind. To say that a change is "for the better" is quite meaningless.
I cannot imagine myself as physically immortal; to achieve that would seem to me as traumatic as losing one of my senses. I even know which one: my proprioception. I would, morally, need to constantly watch my actions, having lost the easy guide upon which I so often rely. I would stumble frequently, and be unaware of it until I found my perceptions askew.
But I would guess that we will alter ourselves, early and often and deeply. We will give ourselves the traits that so many of us dreamed of having as we read science fiction. Perhaps we will become Slan, as it were. But we should remember that those stories only made sense in the context of a greater humanity. When that reference is gone, to what shall these creatures compare themselves? They will, according to our assumptions, govern themselves by a different Game Theory. They can afford to alienate; with enough power, they can afford to destroy recklessly. I mention this not to create fear of our offspring, but to see if anyone can, by the previous assumptions, accuse them of wrongdoing. If morality exists only to help us survive, they will be no more wrong to destroy those useless to them than we were not to destroy such people, who were not so useless to us. They do not, after all, require our presence, and gratitude has little enough value when no more such gifts are to be given. If, however, there are eternal truths and absolutes, they will be just as wrong to destroy us as we would be to destroy the most insignificant person.
Naturally we will be able to, eventually, hardwire either belief in our children. And, naturally, if they truly have reason, they can overcome such hardwiring. To hardwire a sort of immutable Kantian system in them might preserve us, and thus be moral under the assumptions, but they would not be descendants of the human race if they did not possess the ability to alter themselves according to their reason. After all, we altered them before their birth, according to ours.
If we leave ourselves as men, we keep our morality, but lose the chance to find whether morality is universal. If we risk changing ourselves beyond recognition, we leave our morality behind (perhaps! but only perhaps!) and find ourselves adrift, without the tropes that guided us so successfully. If we set morality upon them as a safeguard, we protect ourselves but destroy them as Beings. Our only moral option may be to create the race that will supersede us, and hope that they don't.
