I always found the most effective punishments to be those that He personally tailored to suit my specific issues/problems/likes and dislikes.

As example, some subs walking around without panties....that, to me is a horrible and extreme punishment.
I'm a masochist, so any pain punishments won't correct behavior, but will give me a serious case of the funsies.
Well, except if He mixes it with His own brand of mindfuck, personally focused on who I am.

Thus, while ideas on punishments is a good way of erm...getting the creative juices flowing, it can never effectively change behavior if it doesn't have an element of the personal.