Strikes me as an implausible development, unless there's a seriously convincing middle part between "violent firebrand with godlike powers" and "mature, gentle, Jesus-like adult with godlike powers" that they've come up with. And the reason I find that implausible is because the godlike powers part makes any sort of personal growth hard when you don't have any respect for human institutions in the first place.
It's likely his first run in with kryptonite will teach him a little humility.
That's the thing. Superman with no intrinsic moral prohibitions about, say, willfully and egregiously violating basic laws like "don't batter people without a justification" seems likelier to react to "you tried to kill me with kryptonite" with an aggressive, not a conciliatory, response.
has a point, and maybe I do just have a dismal view of human nature.