Better ways to store postcards?
 

So currently my gold plaque postcards are in Card Saver IV's and stored in a postcard box. Are inner sleeves worth it to buy and are there better holder options out of curiosity? Also the BCW box is almost full already so I'm listening to suggestions on a better box as well.

I always kept mine in top-loaders and used a tiny sticky label at the top of the top-loader so that I could quickly find the one I was looking for.

Different than toploaders/sleeves, but I use Itoya 4x6 and 5x7 inch art portfolios for postcard sized items.