So here's a cool combo I discovered the other day for Campaign Mode:
Put Tireless Ranger on Eleanor. Now she's an eligible target for Wingfoot. This means you can declare "Treachery" every round, and if one ever comes up ready Eleanor to cancel it. You can do this indefinitely, so far as I can tell, so it effectively neutralizes all treachery cards.
Pretty neat! I'm not finding it too useful in my solo campaign, but I bet it would feel horribly broken in 4-player.