Why is there no actual ending if you let Delilah complete her ritual undisturbed? All they would have to do is have a short voice over of still frames of Emily Kaldwin on the throne.

I understand that doing nothing isn't supposed to be canon (and I assumed it wasn't before finding out there is no ending) but why couldn't there have just been a short monologue by the Outsider about her rule over the Isles?

Because the history of Corvo, I guess. Meaningless, I know. xD

Maybe the developers wanted to complete Daud's fate and show us that he's the real savior of the Empire.