Hello,
About 5 years ago I bought a large iPad (around $1,000) and began converting all of my music to forScore and now honestly, I would never go back to using paper music for multiple reasons. I still keep all my old paper scores, and occasionally buy printed music, but I immediately scan it into my device if I decide to begin practicing / playing it.
Most classical music is now downloadable and once it is on your device you can use an apple pen (another $100, sigh) and finger / edit the heck out of any piece. Anything you can't get on line you can scan into your iPad with a free scanning app (I use it often for older paper pieces I have with fingering and notes).
Organizationally, you can classify your music into Genres, then sub categories like Labels and Tags. Every piece has a name and a composer so for example if you want to see all of your Chopin you just select that composer.
The chief benefit you have (once your repertoire is on the device) is all of your music is on your iPad (really in the cloud) and wherever you go you can bring it with you. When I play a recital or for example if I am playing in church, I do a playlist under a label I create and all of the pieces are there one after another in my order I choose. The only disadvantage of using an iPad I see is that only 1 page shows, so if you play by score you need to turn the page, but honestly turning a page is so easy (you tap the lower corner) and you can also by a bluetooth pedal.
As far as keeping your repertoire "playable", I had a piano teacher once say, the better you learn the piece now, the easier it will be to re-learn it a year or two from now if need be.
Good luck!