Dishonored DLC's

The Knife of Dunwall is the only dlc interesting for me because it's a part of the story from the game (you play like Daud), the other two are lighter addons with some weapons and time challenges.

I'm kind of wondering the same thing. I've played through the main game almost twice now (I'm almost done with my no kills, no alerts, no powers run) and I have to say that although it's a great game, I've maybe had enough. Are the DLCs varied enough to warrant buying them?