Throughout the lifespan of a project involving multiple files, not only is the main project file changing, but sometimes other related files. It would be awesome if visually, you could represent the "current folder" by perhaps clicking on it and selecting a "tag" (sort of like folder colors) but for status. This way, you could know, quickly, where you should be working and instead of color (which is sometimes meaningless) you could map real concepts to the use of the folders. Just a suggestion, Apple...