Well, as far as my teams shooter goes we generally used an angle that best suits situations that we know we can be sucessfull with. There was a couple of things that we learned during the development of our shooter.
1) It needs to be able to change trajectory (however you do it)
2) you may need to change speeds
3) you need to be able to shoot over 60" before the ball leaves the frame
4) Taking a little experience from rack and roll, Set positions are key to being able to reproduce a shot
Those are just some things we learned, aside from shooting is going to be only at most, half the game anyway.
