Good stuff.
This might seem a bit harsh, but I'd just like point a few things on which you should focus in order to get even better.
Proportions are a bit off in some drawings, but nothing major.
As Jubal said, you should practice drawing faces. And that's the hardest part. It's not easy to draw a convincing face.
Shading. I'd really like to see some of your graphite pencil drawings.
Character poses are very good.