OK Last one about this! I promise! Him being healed made him a perfect clone, which obviously took away the madness from clone degeneration, and in my mind, arguably induced a progressive personality change. Note that he only really becomes quippy and heroic as the book goes on and even then it's not the same style of humor of Spider-Man. My way of seeing it and based on Yost's interviews is that, when the degeneration cure kicked in, he was rushed by a semblance of Peter's conscience, buried behind the madness; what would happen if Peter Parker woke up one day and realized he had been a murderous ##%$? Kaine's frequent breakdowns amount to that. And then there's the (anti)hero's journey, etc...