Your use of gestural lines is very good, as is your weight. From what I'm seeing you excel at composition, and these could easily be considered finished from my perspective.
The only issues I've spotted are with your third drawing from the top. Something about it turns me away. It seems to not fit in with the group when it comes to style. If I could wager a guess, I'd say it's an earlier drawing than the rest of them considering how much more free your strokes seem.
Add some value to your cheeks, lips, chin, and make them stand out a bit more with just color and not pencil. The results may surprise you.