Quote - The only other real possibility that I can see is to have 3 categories instead of 2. Say for example 'no nudity', 'tasteful nudity' and 'in-your-face nudity'.

There is that word "Tasteful" again.

Please define "tasteful" so that the definition and understanding for everyone is the same?

IMHO it's not possible because as I said before it's a highly subjective word because everyone has their own views and beliefs based on a variety of factors from geographic location to moral upbringing and everything in between. What is tasteful to you may not be to me, etc.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi