I use a pinky hole in all my stuff. I started by accident (bought a used ball with one in it, and just kept it) but as I've gone along I've found it to be great for helping with wrist tendinitis.
Not only do you distribute the weight more evenly across the hand, it also increases the lateral stability of the ball. It can't wobble left or right in your hand as easily as it would otherwise.
I don't have a problem with my hand clearing the ball or anything like that. It is similar to tucking the pinky but I think it offers even a touch more control.
A quick how-to-drill: Get a quarter scale/Pro-Sect, position it directly at the center point between the two fingers, then drill a hole 20 degrees down from the ring finger and leave a 1/2-inch gap (or "bridge) between the ring and the pinky holes. Remember to pitch away at the same pitch you used for the ring finger and then add reverse pitch 1/8 to 1/4 from what you drill the ring (i.e., if you drill the ring with 1/4 forward, you'll drill the pinky at 0). This won't work for everyone but it's a good starting point.
Jess