First off, you've done a very good job with this face

Which is the definitive version? The middle one or the right one?
The middle one has an outline and some freckles/noise, so it's unclear...
I like the right one better, so I'll base my critique off of that one
Hair:

• Hair doesn't have same color depth as the face (just 2 colors instead of 4), dissonance of details?
• Shape of some of the hairlocks at the forehead is unclear.
• Some locks of hair change in width irregularly. For example, the rightmost one that goes over the headband.
• The headband itself also became wider on her right side.
• The thin hairlocks could benefit from some anti-aliasing

Face and rest:

• Weird banding instance over her right eye (looks like small overlapping circles, can you spot it?)
• Generally unclear shapes; lighting seems somewhat haphazard. I recommend simpler shapes.
• Unneeded highlight on her left shoulder. Cloth is not glossy/shiny
• The left end of her mouth crease seems to stretch out too far away (imo)
• Banding along the outline of the lower part of the face (strips of shades that add no 'information').
• The redder tone in the nose/lip is very similar to another color. The difference is barely visible (very minor nitpick).
• The jaw-line is asymmetric.

You seem skilled with art, so the weird lighting/unneeded highlights throw me off
You should know/remember: the human eye sees less details in darker colors, so one should imitate this in art.
I generally try to avoid using the same color for shades and lines, since it reduces readability.
Of course, it remains a very valid approach, and many people make it work regardless