love the sketchs
You could ad some fancy border to accent the faces more, useful in teaching others to draw as they appear to be attempts or works in progress. They're great because the show artist in the middle of the drawing process and show some of his skill levels and abilities. You can't really give advice or suggestions on these because the artist is clearly in the middle of a learning and creative process and the final piece of art could go anyway.
~~THINGS TO IMPROVE ON~~
You could ad some fancy border to accent the faces more
~X~