I agree it's a very interesting and lovely picture to study because there is so much you have to consider with this, most people find it hard to draw (in this case pixel) women becuase the amount of care that has to go into the femininity, especially with children theres a fine line between the likeness boy and girl. It's so easy to accidently make a young girl look too old, masculine etc. Theres also the likeness of an oriental to take into consideration. I like what you've got so far, there are some good traces of observation but still a lot still that could be improved on.
You'll have to forgive me if I don't make sense atall, because there's a lot going on it this
I don't think you're making most of your reference picture, in terms of positioning, posture and lighting you're pretty much on the right tracks but the use of your shades seem to be more of a device to add depth to this than it has of being true to what actually occurs. Your character looks like a young black girl rather than an asian, it's because your tones become dark so rapidly with any shadow of contours. You can afford to be much more suttler and use you're darker shades more for key contrasts which make the image easier for readability.
Hope you don't mind I worked on this for about half an hour to show you what I mean.
With the face firstly, there isn't anything too complicated going on, so there's no need for overshading it.. maybe slight dithering to help bring out the shape of her face but it's should look clean and smooth, your dithering on such contrasted tones just adds an unwanted texture.. Also I don't think theres any need for the near-to-white tone on her face because it only makes her look shiney.
I do think using some Aliasing techniques on this is essential because it will make this overall look much smoother and you can trick the eye into seeing details such as stray hairs and especially making the eyes look much more believable.
With the clothing you should really again keep the heavy dithering with the darker tones to a minimum and concentrate on what you actually see.
I tend to start with the lightest shade with lighter areas and work on the darker shades one by one, and the opposite for the darker areas. The hair for example I'd advice you start with the black and add on lighter shades.
I tried to add in the legs roughly, and quick backdrop from the reference, dnno why im sure you won't focus on the bg but it'd make more sense to the viewer.
Also I think you're palette need re-adjusting, I found two of the darker shades were just a bit too close and two of the middle ones were too far apart, im sure it would't take long to fix and it'd be much easier for you to use.
Im not going to atempt the forearm and hand, because I won't pretend Im any good at their anatomy so hopefully someone else could give you some direction.
Help atall?
-Ter