How you organize your files will ultimately depend on how well you organize in your mind. Some people are great at organization, and others, well not so well. As you contemplate your way of organizing, talk with family as well. They will ultimately inherit your system of photo organization down the road. Will they understand your file organization?
Over the years of working with folks on this, I have seen so much disorganization of their scanned files. Files have been seen inside of Windows System folders, in the "root directory", Program Files folder, and so on. These files essentially become "lost" when they become so scattered. Scattered files are also very hard to back up when they can not be easily located.