"Open, fun, lacking in structure".
That is why Dishonored fails as a stealth game. It feels much too loose, like you can complete the level by just sneaking through the shadows. And if someone sees you? Not to worry, just stab them. I know people don't want to see a "game over" screen anymore, but there needs to be some incentive to do things properly. The levels could have been randomly generated for all I know. Give me Splinter Cell or Thief over Dishonored, at least those games had consequences.