I get what you're saying, but how do you do the important things like: find all pictures of Aunt Jenny; find all pictures of Aunt Jenny and Mom; and find all Christmas photos from dad's side of the family? Or whatever. My point is that a folder structure doesn't get you any of that. You have to find them all manually, and then when you're done, you still have to do a bunch of work to answer other questions. If you're doing anything interesting with your photos (as opposed to just filing them away and never doing anything with them), then why not get a DAM and make managing your photos a million times easier?
But you like your folder structure, huh. Ok, well try this thought experiment...
Put a photo on an external drive. Put it anywhere that makes sense to you. Now, pick up the drive and point to your photo. You can't. You folder structure is simply a graphical representation of the bits and bytes on your drive. It doesn't tell you where your photos are, it just helps you access them. By the same token, a digital asset manager (DAM) does the same thing, only it allows you to quickly create ad-hock groups of photos to suit whatever situation you're in. For me, I use my photos mostly for calendars, holiday slide shows, and family event slides.
If your system works for you, then great. More power to you. But I simply don't believe that a folder structure can help brows, categorize, and group photos in multiple ways. YMMV.