So Dishonored is my top fps stealth game of the year and im already starting a second play through! But honesty this game has so much DLC potential. With all the books and storys within the game a continuation new campaign can be made. What is your opinions on this?

Yes i agree with that a DLC should be done to make more scenarios with Corvo with a more detailed story. It is too straightforward in the basic game.
Some mission/infiltration could have been done in the Lord Regent house to find documents, or other places already done.
Also the Trailer 1 had a Character something of a Minister for Security or Urban Guard but wasn't in the Game...
Some mission are needed in boats, Warships or ships used for the Whale hunt. There is plenty of documents in the game about that and no scenario were done.

Maybe there could be a DLC where you play as one of Dauds (or what the heck ever his name was) assasins, so you could have a different set of powers and equipment (teleportation instead of blink, that green beam that they used to keep you from saving the empress at the beginning, those dart shooting things they have on their wrists etc.)