Additional custom library feature

At present the Kodi library is limited to the basic mp3tags. I consider these far too limited to do a quick selection and want to add my own tags.

Example: how can I differentiate between ten recordings of artists playing Chopin preludes, or find the right version between the dozens of live performances of a Stones number?
In my music cabinet I make this selection based on location of the CD and often also based on the side color of the box. I typically forget where a specific performance was given (was it Fillmore, Atlanta, Carnegie hall, etc).

My ideal solution would be a graphic drag/drop and swipe solution allowing me to “throw” any albums or songs in a database folder that I tag in my own way (“poor recording”, “best performance”, “old albums”).
I’d like to be able to browse the library/database using keywords or quickly swipe through my music “cabinet” in the same way I browse through my digital shelves with e-books or search my image collection based on the name of a friend or any other tag that I’ve created for an item in the image.

We know that Google/Picasa etc can easily do this for images and books, Why not for audio?
Kodi has a lite database function so why not expand this with custom tags or meta words allowing for better filtering. From my perspective there does not need to be a compatibility with the limited mp3 tags. It may also be implemented using a hashtag option within one of the mp3tag fields, such as under comments. In that case I can filter using #great#live#stones#satis, for example to find the songs I am looking for.

Am I overlooking something and does this already exist?