Hey Jos, I'm pretty much in the same position as you and have only wkends and evenings to draw -- if you are persistent enough, your efforts will pay off! You are gradually improving. I'd suggest focusing more on accuracy of line and less on shading for now, as this would really force you to pay attention to angles, length and negative space, plus accurate rendering is very difficult without accurate line (whether in your head or on your paper.) Also, when you are doing studies, really *study* what's in front of you, don't take shortcuts. If you see a certain shape, draw it exactly as you see it, not just an approximation.