I enjoyed Kingdom Come and still do. That's because I honestly don't think Waid was making any kind of commentary on Superman as he functions in a story or what would cause him to abandon his mission. Kingdom Come isn't about Superman quitting or why he would do it. It's a commentary on the industry at the time. The comic reading audience seemed to want those violent heroes and that 90's extremism. Characters like Superman were seen as old fashioned, out of touch and too simplistic to be effective. So really, KC is just meta commentary on the industry. What happens in KC? The world wants violent and "effective" heroes, things spiral out of control, then everyone realizes that they need Superman and his "old fashioned" sensibilities. It's just Waid's way of saying that Superman still had a place in the industry at that time and while it may seem like he was going away, he'd still be there. So I actually don't mind this version of Superman or the story told.
Now, True Brit and Act of God, those were some truly terrible versions of Superman. Not a fan of Injustice Superman either as it caters to the "Lois keeps him grounded" trope.