Just a few things I think might help (some of these might have been listed already, these are just my random thoughts):
Eyes further apart (about one eye-width between them; they look closer right now)
Eyes flatter on the bottom and more rounded on top.
More of a smooth bridge on the nose (right now it looks like she's wrinkling her nose because of the crease around it)
Smaller cheeks
Maybe spread the entire face out a bit? (Make the eyes, nose, and mouth farther apart from each other)
Ears a little smaller and higher
Add eyebrows (even if you just have to scribble them on in a paint shop program for a preview image; eyebrows can make a huge difference in the appearance of a face)
Add a neck (even if it's just a quick cylinder. Again, that can make a huge difference in a face's appearance)
Maybe make the head a little taller in relation to its width? Not sure about this one, but it might be something to try.

Don't give up--I think you're off to a great start

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