Oi, why am I doing this? I promised myself I would never touch anything like this...
Anyhow I'll try to get this done quickly.
The shading's a bit better, sure, but overall the piece lacks unification. If you look in a certain topic about a beginner's first sprite with shading, and scroll down a bit, you'll see EyeCraft's humongous (but potentially extremely helpful) wall of text describing how hue-shifting makes color unificat--wait,
here it is.
And this is the (also quick and sloppy, but hopefully proving a point) edit:

What I'm going for here is essentially telling you that each color ramp doesn't agree with other ones, seeming especially separated from eachother, a lot more than they could be. For example, the blue garments, which I may point out there are very little of, are strangely dark--contrasting with the skin--and basically lack any hue-shifting. The hair's a bit closer to where it should be value-wise but, once again, lacks hue-shifting, and almost looks like a wig on her head. Both are also very saturated across all values.
Also on the topic of hair and wigs, you seem to be defining each strand--or rather, group of strands of hair, resulting in unsightly spikes, which is what beginners tend to do. You have to think of hair as more of a blob-like, simplified/ambiguous form, and think of what forces are causing it to move. Is the character standing in a breeze? Is he/she moving swiftly? If so, in which direction? And of course, there's gravity. (Same with clothing.) Then, you don't have to define every group of strands, like you are now--only some strands are necessary to describe which kind of hair the character has. Curly, wavy, straight? Less is sometimes more. When light is applied, texturing it according to the hair type should be the way to go. See what the strokes suggest. Straight hair = straighter strokes. If you have a tablet like me and a lot of other people, good.
Then there's lighting. Once again this is the kind of thing you have to really think about in order to get it to look okay. I find a good technique is thinking about the basic forms your character's made out of (cone, box, sphere etc.) and where, exactly, the light is coming from as well. Also some practice. ErekT was off to a good start, both lighting and palette-wise, so I used his edit as a base, adding shades as I went. If you want the specifics, I added another midtone and a highlight, and went about adding blobs of light and shadow and correcting a few things here and there, adding highlights to places you might want to attract the viewer's eye to (
teehee), and masking unimportant, otherwise distracting things in shadow. Then I added some dithering, as this is a fairly large sprite. And some other things, including adding teeth (she looks... Weird without them, really) and a few minor and more technically feasible design changes (which probably could take "witch" out of the title and leave it with only hent--I'm done).