Also, another thing we could do is a plot involving the chess set. It's been referenced a lot, and it's supposed to be the Deck's usual antagonist - so why not have a plot involving it? Perhaps the Chess Set approaches the Deck to form a treaty to end hostilities. That's something that would take a while, and there could be "delegates" for the Deck members to interact with.

There could also be some kind of mystery to solve, like the Andrew plot, but preferably without another murder. Maybe an object of some sort that needs to be found?