Honestly the only Joker backstory/explanation I'd ever want to see would be the Whatever Happened to The Caped Crusader one where Alfred dresses acts as the Joker and commits crimes to satisfy Batman's mania.
OP, sorry, but I really dislike your interpretation of the Joker.
What I love so much about The Killing Joke origin is that he was never crazy, or a drug addict, or abused. He was just an average guy, who after a series of unfortunate events, finally snapped.
That's what makes it so scary. "The Joker" could happen to anyone.