This came up in a recent discussion in the USBH project and I think it relates to the recent discussion here on G2G about improving the Help pages and generally improving WikiTree to be more friendly to new users.
I'm pretty new to WikiTree myself - I just joined in early August, and have been using it a lot, probably almost every day. But just today, I learned that the "Navigate" link on the top of category pages will take you to a list of all the sub-categories. I didn't know what "Navigate" did so I never tried using it, but multiple times I had wished there was a way to view all the subcategories - I just didn't know "Navigate" would do that for me. Navigate is not (to my knowledge) used like that commonly across the web. I don't know how difficult it would be to change or if other people feel the same way I do, but maybe something like "View All Subcategories" or "View Category Hierarchy" would be more self-explanatory and help newbies find their way around these pages a little better.