This game is hard enough to learn without house rules.
Since they are likely to have a limited model pool, it might be good to limit yours as well. Taking a Master's full crew is good, and try to stay in theme. Also, try to leave certain power pieces at home (Why, exactly, is Papa Loco running around with Sonia and a Death Marshall?)
I emphasize the "don't be a jerk!" mentality. I think if you're playing against a new player, discussion beforehand is a good thing (You're running McMorning, but Santiago here has this ability where he can pitch a card to remove poison). Also discussion after the game is a good thing: talk about the "good plays" and the "bad plays".