So, I just got the basic game box, and played it for the first time using Stark vs. Baratheon. After a couple of games, Stark seems ludicrously overpowered; they have loads of deadly characters, strength boosters (winterfell castle et al) and, in general, very difficult to stop. Baratheon seemed very underpowered by comparison.
Are we missing something? If not, does the balance get corrected in later expansions?