iTunes functionality built into OS?

I have been using itunes for as long as I can remember, I think I had one of the original ipods and used it then. My library is a mix of my own materials (movies, clips, tv shows, music, books, audio and photos) and store bought media. The library contains somewhere around 50,000 items.

Does anyone else find itunes less than ideal for maintaining it? Sure its great to makes playlists and modify tags and metadata to help find things; but why hasn't iTunes evloved? Why can't itunes be part of the Mac OS? You right click on a file or folder, and 'tag' it as being part of your itunes library. It then becomes instantly shareable with all your devices, without having to load it into itunes, then file it away, then sync your devices. Photos are probably the worst, they dont become useable in any devices till you physically sync your library.

Being part of the Mac OS, the content is cloud shared, and instantly availabe to any device, anywhere.

just a thought.