Regarding that drawing with your finger issue, I was thinking about that.
So the problem is the screen sees your finger as a squishy smudge of contact area. It can't tell which way is the "front" of your finger so you can see where to draw. BUT, you can solve that by using two fingers together. Just like on a multitouch trackpad, you can easily draw with two fingers. The two contact points would form a line and perpendicular to that, you would draw a pointer and the tip would be the active drawing point. It will be like you have a stylus coming out of your your two fingertips and give you precise, visible control.