The pixeling is good overall, the form is nice and it is dynamic and has a nice flow.
You really have to work on your colours, They are extremely bland and also again, no hueshift going on.
I would also advise not to use pure greys, in most cases it looks wrong and if you use it you really have to be good with colour and know what you are doing.
I made a colouredit, bringing the count down to 16 colours (including transparency) I took some liberties with the hair.
Also some parts looks a bit rough and the face looks kinde skewed, the perspective of the side on the left is off.