Who-ho-hoa! 23 replies already!
I think you may be confusing him, jams... I agree that value is more important than hue-shifting, and that it should be applied first (this usually means the first version is in black and white and color is applied afterwards). But it's quite common, in fact, more often than not to see hue shifting in well-made pixelart; even some realistic ones, for some reason, but especially in stylized pieces like these. It'd be unusual to not have any hue-shifting even under certain lighting conditions, but if you feel that's what you want to do, go ahead.
Value's the main concern here. They're quite low on the hair and shirt. Other than that, the light source appears to be overhead but isn't very defined,
partly because of the values. From a 1x scale the shirt almost appears to be pillow-shaded, whereas I imagine it a a cylinder, or even, for the sake of keeping things readable, a plain field of color.
To preserve readability on something of this size, keep pixel clusters large. Don't define details using one or two pixels; for example, what you've done on the character's shoulder pads. Same with lighting; keep it general, you don't have to click around forming lighted strands of hair or folds of cloth with individual pixels. If you do, try to buffer (smooth) things out with another color until it looks okay, but don't use too many of course--one buffer color should be fine for this size--and don't forget to avoid forbidden practices of banding and pillow-shading.
You have some unnecessary colors as well. Note some have been adjusted to be used for more than one purpose; for example, I got rid of two shades formerly used for the sprite's pants. Since it's harder to distinguish between dark colors at a glance, I used the darkest shade to fill in for both hair and pants, and replaced the lighter shade with brown. They're single pixels, so they'll be harder to notice immediately, although they do give the pants a warmer tone... Similar to the rest of the sprite. Another thing I did is used gray to act as sky speculars on the hair. You can read about those, among other things,
here.
