In the game there is of course the basic world area. Then, there are instances, which use the instance manager and are located inside the world itself. There is also, a 3rd location type, for example the Bergman's_Burrow which are not instances, but have their own map. What are we, or should we refer to these inner locations as?
Well, I think we should consider all of these under the same super-category of "locations". Then I believe we should have subcategories of sectors (which includes pseudo-sectors like Deadfall and Terminal Woods), and under those would be the various "counties" or "regions". And then lastly all the other individual places like the caves, towns, etc, should be considered a basic "area" category at the bottom of the category tree for locations.