the Purple blue is better. Might wanna work on that cloth a little. And the length of the robe is a little short, or high-watered as some might say - the bottom hem should come down more to rest on his feet, not reveal his ankles.

the robe is short by choice.
 what do you mean by work on that cloth? Im not entirely sure what cloth your talking about, the rendering on the hat, or the cloth of the robe ect.

this is really big and something pixel art's not really suited to, my first piece was a dither mess as well and i never finished.

im saying u shouldn't go overboard trying to create smoothness in big pieces for pixel art. and that doesn't go for everything of course, but for drawing a face, id suggest a more stylized approach, like that "leader of the blades" picture that was made quite some time ago. the piece itself is quite nice, but its just not a very good subject and/or size and/or approach for a pixel art piece. why not just use brushes and have a much nicer piece 100x faster? try to think of a piece that would be better suited to the medium. or you can continue on this and probably never finish.

update:

your trying way too hard to do things the hard the way!, that last one was pretty good, but even still you skip to the rendering phase (shading and adding detail is what it means, since i now know you're learning English) way too early. drawing with one colour to get a nice form, and removing from that form by drawing with the bg colour over it will get you refined shape that'll look nicer than lines with a fill like you're doing now. you can render all the details u want to later on and we can help you with that a bunch!