Hi there,
I've picked up the core set and a few deluxe expansions (Kings of the Storm, Lords of Winter and Queen of Dragons). However, I'm a bit loathe to start adding cards from the expansions into the decks, given that I want all four to be reasonably balanced and I don't really have much in the way of decent cards outside the core set for House Lannister. Are there any expansions that you'd recommend I buy to get House Lannister up to a level playing field?