King knows how to traumatize characters but he has no idea on how to have them overcome their trauma and become better. That works with certain characters(like Vision)but not every character is suited for that kind of story.
Ignoring the botched wedding, King's biggest weakness on Batman is that he's turned Batman into an ineffective and broken hero who can't save anyone, alienates his allies and makes Gotham City worse. Other writers have written Batman as 'broken' but despite being broken in those runs, he was still able to be a force for good. King's Batman is too hurt and broken to be effective.