Let's accept that point and look instead at something Dr. Erskine says to him in Captain America: The First Avenger:
"Whatever happens tomorrow you must promise me one thing. That you will stay who you are. Not a perfect soldier, but a good man."
If we must assume the best of a former sinner that repents--whether its of adultery, theft, murder, or anything else--then we should assume the best of a former sinner that repents of transhuman alteration. If he repents and confesses, then he's not a sinner now. He sinned to some degree when he volunteered to be altered, but he isn't sinning simply by existing now in that altered state. The post-abortive woman is not sinning now by walking around as a post-abortive woman. There is always a way forward.
Does Dr. Erskine's request apply only to the transhuman Captain? Certainly not. He implies something very true--and very easily overlooked--that goodness is more important than intelligence, beauty, or strength. (Rabbi Joseph Telushkin challenges parents on this point in his video through Prager University: "What Did Your Parents Most Want You to Be?") He may be making Captain America powerful, but he cannot make him good. That is the real difference between Captain America and the Red Skull, between Iron Man and Iron Monger, between the Hulk and the Abomination. Do they take what they have (from good means or evil) and make good choices or wicked ones?
Dr. Erskine also recognizes that the good man, not the perfect soldier, is who Steve Rogers is. His physical state or mental state does not connote the state of his soul. The person with an 80 IQ that seeks for God will get to Heaven, while the 163 IQ that doesn't repent of mortal sin will not. A wicked but powerful Red Skull is weaker where it really counts than a physically-inferior Steve Rogers. No, we're not just souls riding around in bodies; we also are our bodies. However, "self" does not spring solely (soully?) from our physical or mental limitation. That is not the "me" on which I'll be judged, in the end.
More on this coming soon, when we'll talk about goodness and power in the Avengers.