The skin is too light and samey, don't be scared of using stronger colors, I had to draken everything so I can have more room to shade and highlight areas. The mouth is cute, but too small, made it slightly bigger. the nose was from the wrong angle.
they eyes are stunning, but the eyelashes are too messy, the eyelashes grow on the direction the skin takes. and btw skin wraps around a ROUND eyeball, you can see that on the left corner of the left eye. Also the style of the eyebrows doesn't match the face. you can do a lot with the eyebrows to show an emotion as well, they could be very expressive.
Cool trick: to make sth brighter make things around it darker. which is what I did with the eyes. the top eyelid drops a shadow on the purple, use the shadow to create more contrast around the eyes. I made the nose and eyes a little redder to give the face more emotions.
fixed the shape of the neck. nicks get a little wider as we go down, they don't curve. and finally the coloring of the hair and the lines of the hair are not going together, like two separate people did each without seeing what the other person is doing. colors need to add form to the shape, to show where the hair comes out of and in what direction it's moving. I hope this helps you! your colors are cute I'm sure you can improve so fast!
Here's a summary: 
