Why are they so bad?
They are very uninspired and the humor (which is a big part of the game) was flat. The only funny part I found was the horsless-headman bit. That's it. The new characters are not appealing, the new buildings are confusing, and the game mechanics have not changed -not that they need to.
To give you an idea how bland they are: I have played this game every week for the past 8 months or so. I play the main story every week. I have not bothered playing the dlc again after I finished it, and really couldn't wait to get done with it the first time around.