Split: Parent and Child Categories selection and display

So basically, this directory system works with a flat level of categories only.

The popular category widget is useless. I want CHILD categories listed on the category page not popular ones

I might have a regional directory with parent categories

Adult Services (Child categories – Gay Bars, Strip Clubs, Sex Shop, Escort Services)
Dog Breeders (Child categories – Border Collie Breeders, Labrador Breeders etc)

If in this directory Gay Bars are very popular…. I could end up with Gay Bars showing up as a link on the Dog Breeders page…. with no links to the Child Categories of this Category at all?

That’s so confusing. And disturbing,

It makes zero sense to have no ability to display child categories on parent category pages. Google cant even find my subcategory pages. Its a massive oversight and renders this directory system pretty useless if more than 1 level of categories is being used.

Cant you modify the “Popular” Category widget to
a. Only show children of this category.
b. Show a maximum of “X” categories visible at the top.
c. Show the rest(if relevant) of the subcategories by clicking on a “show more” button?