I made a quick edit of your wizard:

I feel like you're relying too heavily on dithering as a method of shading. Dithering is one of those things that is easy to learn, hard to master - it's a simple trap to fall into. For sprites like this, using colour block shading is probably going to net you better overall results.
Most of your shades don't have very much contrast. To lend a feeling of volume and depth, it's better to "make it shiny" - don't be afraid to use very light colours to indicate ligh. That being said, it's better to avoid pure blacks and pure whites. They just tend to feel "off" in an image, though there are of course exceptions to this. In your image, pure white especially felt strange given the amount of shadow and the sense of ambient darkness.
Robes are flowy and don't just poof out and sit still like a hoop skirt. Your magician is meant to convey a feeling of mysticism, of eerie power! Their robes should always have a sense of movement and... possibility? to them. Try to avoid making them feel stiff. The arms, particularly the one that isn't outstretched, felt rather robotic and stiff as well. I made the shoulder more rounded and the arm moved a bit further back.
Your hood felt unnatural in how it lay. The top lip should bend down a little bit more and fall around the face - or black abyss, but well.

I'm not totally happy with my edit of the hood, as the top lip feels a little thick, but it should convey the idea.
The face felt like it was facing a different direction than the torso and the hand. I reshaped the face-abyss to appear to be looking in the same direction as the hand and torso.
I would also recommend trying out some colours! I assumed you wanted to keep it more or less grayscale, so that's what I did. Here's one option of how you might colour our intrepid wizard, however.

Generally, when shading with colour, just keep in mind shadows should be more blue and light more yellow. Not a hard and fast rule, but for when you're ready to start looking into that.
I hope this helps a bit, or at least gives you some ideas! Happy pixelling
