I only played the good side, but I observed that the Outsider is a neutral party. He merely watches people who change things. On occasions he grants those he watches power, but it's up to the individual to choose how they'll use it.
In the end, he's just a dumb whale watching the world react to him.
Dishonored asks a question; How will you conduct yourself? Will you kill to get what you want, or will your actions?