It may help you to work with a less saturated background surrounding the sprite, which is what pixelation's color scheme is chosen for.
Other than that, i edited:
- The eyes, it's difficult to make eyes readable when the sprite is so small and eyes have to be smaller
- you have an extra green used for about 3 pixels on the bra and right shoulder
- the cape had its own palette that was pretty close to your main orange/brown ramp
- the skirt shading didn't make sense to me
- the boots could be highlighted like this if you wanted to show the light was really strong.
- most importantly, don't be afraid to put colors next to the outline.