Foam Storage trays

[The Royal Hajj]

You've got it. However, I think the decks would need to be stored in a separate pigeon hole to ensure the foam to base fit is snug enough. Since each deck will have different amounts of cards in it, stacking them in with the bases would cause to much play.

[Gunner]

Having a separate tray for cards and one for equipment wouldn't hurt. Or a combination of both.