I have white tape on th front and back (1" wide, one at the front two at the back). In addition I also put two pieces of tape on my thumb (Brunswick fitting tape). I find that the right amount to get my hand comfortably in the ball. I don't have hanging up problems unless I turn my wrist over, which will make the ball hang either way because of the oval.
If you have tape just on the front, it might be the case that there isn't enough friction on the back of the hole, causing you to subconsciously think it's going to fall off, making you grip a little, hence the hang.
As the others have said, it's a very personal thing, and only you will know what feels right for you. It should be tight enough that you don't need to grip the ball tightly to hold it on, but not so tight that you have problems getting it into the hole in the first place. This will ensure the smoothest possible release, and allow the most relaxed armswing.
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Reporting from England