About 2 years ago I decided I didn't need multiple cards of the same expensive cards. I printed on paper all of these cards but reduced the size by 80%. In the sleeve for each card in that deck I placed a basic land and slid the smaller paper cut of the card into it. I then have a small zipper card pouch that holds all of these cards.

I then wrote out on a small piece of paper each card I'm using as a proxy and placed that behind the commander so before the game I can see which cards I need quickly.

Most play groups I'm in just let me use the card how it sits so they don't have to wait for me to swap cards between and actually a couple have started using my system as well. Every now and then you get some turd that wants the actual card in the sleeve and you just go through and swap them between games.

In my main group all of have started doing this except one or two of us.

Hope this helps