Huh, wow, I never would have guessed. Thanks for posting the solution I'll remember that.
1. Remove cards you don't use/care about and move them in only when you need to.
2. I'm not sure if you know this, but you can move the cards back in the chara folder while the game is open and it will refresh/add them in a couple seconds.
3. Manually Drag and drop the ones you want to load in the game window (
You must be registered to see the links
) and keep them in a different folder outside of the game's.