First, I must say that it is absolutely stunning. Definitely one of the best Jokers I've seen.
My only critique though, and I dont know if that's because of the lighting, or the contrast in my computer at work, but from what I can see, the expression looks sad.
Maybe its the lighting, but if it isnt, if you can make it look more stoic, that would be perfect. Its just that sad is definely a wrong impression for this figure. He's a symbol of anything anarchy so he has to have a stoic, or angry or playful expression.
And yeah, I would be curious too if it can be made in 1/6.