Pin placement is not too bad since I started using two pins in the butt end of the knife. I do this because I noticed that if the handle was going to separate from the tang, it would happen in one of those corners. Using the double pins in the butt had an unexpected benefit, it draws the eye in a different way so that if my center pin is a little closer to the front or back it is more difficult to see than if it were just 3 pins in a line.
As far as the shaping, I know generally where I want to go, and I spend a lot of time grabbing the handle in different positions and seeing how it feels. I usually do one depression at the back and a longer one at the front of the handle meeting somewhere around the middle pin, depending on the length of the handle.
Hope this helps.