Klaus Gunther Herzog
This idea stems from my negative impression of 3 particular cards... Tenno won me the game twice, and I'm not sure I like it.
Basically three cards that let one avoid being targeted in Battle A, Battle B, or both. Since there are 21 favors and only 18 of them will get used (3 per season x 6 seasons), you COULD simply remove those three cards and have new favors come up every season.
BUT they're not necessarily BAD cards, just anti-climatic in the last turn. So, what if...
Last Turn Battles
If a "no combat" favor card comes up in Winter of Year 2, replace that card with another from the deck.
Worst case scenario would be that all three of those cards come up in the last Winter, all would be replaced, but STILL with no duplicates, as there are three cards that, in the existing rules, would never see play.