this piece was designed to be viewed at 2x.  loooove the hair at the top

I really like that particle effect, the hair looks very smooth and has a nice flow. Anatomically is okay, perhaps I wouldn't have even drawn her foot (I don't think it's visible from this angle) and maybe the neck a little thinner? Other than that, I really like it, and the simple background makes the eyes focus on the figure.

Heh. You took my particle idea (that probably wasn't original) and made something way cooler than what I thought off (witch brewing potions)

Yes, what you've done is good as is. The background helps focus attention on the main figure in the center. Speaking of figure, well done on the anatomy. I'm not brave enough to do drawings like this, nor as good. The biggest problem that I can spot is her left foot. The position that it is in now is unnatural and would be extremely uncomfortable. Her heel should be covering the bottom of her foot from view.

What you have now looks great! By the way, you still have one more day to work on it.