Hi Amy
Looked at your piece with fresh eyes this morning.
Two small areas I think can be revisited.
One:
Where bottom of skull connects behind her ear, there is a surface plane there.
Not too visible on photo, but very important.
Soften outside neck line where it runs into ear.
This will put it behind ear in subtle shadow.
Will also make the neck more feminine and graceful. (Like Audrey Hepburn’s)
Makes a little indent where skull connects to neck muscle on outside line of neck.
Two:
Make hair above forehead, right side, more pronounced. Hair on right side near forehead needs to be fuller for the 3/4 view. Subtle shadow where hair and skull connect. (Top of right forehead, soften edge, will give it roundness.)
Just nit-picking. But sometimes little subtle details surrounding face really add to the character and mood of the face.
Try what I said on a clear overlay on the head face and neck - if it doesn’t help then disregard it.
Really beautiful face with subtle emotion on this new one!
Nice Job!

Take Care
Glenn