Since the site upgrade made adding new categories possible, I'd like to suggest a category for locations/settings. For tags such as forest, beach, cityscape, and more broad inside, outside, seaside, underwater, etc. Would also be applicable to specific locations, such as Paris.

Nearly all of the posts that feature a background can be tagged with some location, so this would make it easier to see at a glance if the posts are missing location tags (the General tag list is getting very cluttered these days), and would be useful for various tagging projects (if some search such as loctags:0 would be implemented).