With all of the "Cast Joker" threads, this one actually asks some new questions. I like that.
I think we should stay away from camp, for the most part. This Joker has to be PURE EVIL. We want people to enjoy the fact that he IS The Clown Prince of Crime. He has to be purely ruthless, his jokes have to be more cruel than cute, and his eyes have to have the look of pure insanity...because that's what Joker is...he's insane.
Yeah, we love to laugh at him sometimes, and there would be moments to do that, but the heart of the character has to be of pure fear & hatred. It's ok to like him, but like him b/c he's evil and likes being evil, that's it.
I think a purple suit is something you can't touch...but I'd like to see a variation. He's always wearing straight purple with green & orange, maybe a bit of light blue. Nicholson's wore plaid, a fashion moment of the era. I'd be more interested in a fitted suit that was maybe black with purple pinstripes, or at least purple with black pinstripes. If the suit is all purple, which I think would be the way to go, as easily explained by the suit losing color dye when he falls in the vat of acid, I think a different color combo may work better, but I'm no fashion major. I just think he wouldn't wear orange and green silk. Nolan's Joker will probably be more realistic than that, don't you think?
As for his origin, I think they'll parallel his to Bruce's, to create the ultimate yin-yang relationship between the two; they're both the same, but made different choices. Burton tried this, but I think he failed. I don't know how Nolan will tell the origin any differently than Burton did, to be quite honest. Let's hear your thoughts.