Okay this is a really BIG one. A really neat idea for Scrivener would be the ability to import (via your Images folder) a Fantasy World Map (say created with some other illustration or map-making software, like Ortelius), and then it “Locations,” and both it and the Locations on it will automatically go in your “Locations” folder, each with a blank “metadata” page which can now be filled with your own custom metadata which can be . . . well, anything. Images, drop-down boxes, check boxes, keyword lists, and even links to Documents and Notes and Bookmarks.
The first step toward this would be for the external software to capture “Locations” in a form that Scrivener can read, such as OPML.