Looks great Dennis.
You're making huge steps forward with every new sketchbook page. Makes me jealous. =A=
A small note on the last painting:
Play around with her face a bit more. It's the first thing you look at, and beside of her hairstyle, it doesn't look very remarkable. But the rest of the image looks awesome. I love the rendering on the gun and the green/yellow coming from the bottom left corner.
Keep it up!