Very Nice. I wonder what a fan based source book on some of these new areas would look like?
Well, for a start you can check out TalMeta's excellent Sunela region gazetteers here on canonfire, which is the material Scottenkainen seems to have used as the basis for his take on the area.
Just click the search on the navigation menu at the top of the page and type in Sunelan to bring up the articles.