heres a quicky edit i made for you.
hope you dont mind.
I wasnt a huge fan about the checkerboard dither pattern you have going on.
So i thought id share perhaps a different approach.

(mine on left, yours on right)
I played with the iris and eye lids mostly.
Instead of using the checkerboard dither pattern i used a different technique - Dynamic Dithering (DD).
I ended up drawing lots of different lines that follow the curves and forms of your shapes. These lines ended up running into each other, crossing and such, creating lots of broken lines as the dither pattern. There really is no set pattern. It is how your coloured lines interact with eachother depending on the shape its filling in.
by doing so it not only blends like in dithering, but it helps to accentuate the curves and shapes of the image. It can help give more depth and form because not only is your lineart creating the shapes that give the image form, but your colouring now also contributes because it follows those shapes that the lineart set.
I didnt touch the lashes, eyebrow or part inbetween eye and eyebrow because they seemed unfinished. Also, it would allow you to try in those areas if you so chose.
hopefully that makes abit of sense.
if not, i could try and elaborate alittle more.