Add an option to the paragraph styles panel to view paragraphs sorted by the "based on" property.

I'm thinking something visually like the way illustrator displays groups and groups within groups, on the layer panel.

This will save a great deal of time opening and closing paragraph style panels to find out which styles are based on others before you make an edit to one of them. Instead you will be able to near instantly tell which other styles will be affected by your change to one style.