With the leg length, I think it just looks wrong to me because the hotpants disguise the length of the leg. The character's structure is much clearer in the original.

Colour combinations that work in high res often don't work in low-res. This is because high-res art allows much larger areas of colour, and it's easier to read them when they're large. Smaller art generally requires more contrast to achieve the same readability, because each colour takes up fewer pixels. For that reason, I think the increased contrast on the hair is a good change from the original, while the decreased contrast on the skin is not.

I should mention that this piece in particular is traced from BlazBlue Cross Tag Battle, so the proportions are fully accurate, as you can see here:  78.media.tumblr.com/4624b0d010467d067742067f1e1e539c/tumblr_p6rocuSijC1rzso0qo1_1280.jpg

I've updated the image with the more accurate shading and better skin.   I also find the game uses a far lighter shade for the character, but here's the sprite with it matched: imgur.com/82B6Cmk

What's this, a Reix piece that isn't animated? What universe is this :D I quite enjoy your lineless style.

Some crits, in case you're interested:

Because of the low contrast between the skin and hair, and the skin and whie bits, the sprite doesn't read very well. I think using a darker shadow colour for the skin would help with both problems.

The hair feels like it's bunched up under her arm because her body doesn't cast a shadow on it, at least not one that's consistent with the shading on the rest of the character.

This might just be part of the character design, but her thighs look very thin to me, and the knees look to be very high up the leg.

Cool sprite!