It would be very nice to have the ability to exclude certain products from Compendium Sharing on a per-game basis. A GM who is running an Acquisitions Inc. game and a Ravnica game probably doesn't want the players to be able to choose classes, spells and other options that don't exist in the other. Currently, you can tell players "don't use things that are tagged for Ravnica", but often the tags are doubled up or confusing for products that both have entries on "elves", for instance. It would be much handier and easier for GMs to exercise simple control if various compendium products could be toggled on or off within a compendium sharing slot.
