The thought of deviating from an outline has been on my mind.
First, in my debut book, Sigmund Shaw: A Steampunk Adventure, I had originally had the main character work with a girl who had become an orphan. Sigmund would have been like a father figure to her. However, Sigmund already had that role with his niece, so I decided to remove the relationship with this orphan. No problems so far... However, that orphan girl was to balance the story with a female lead character. When I took her out, I forgot to replace that role. Result: the lack of a regular female character is something that many have pointed out as something missing! Lesson learned. The second book, Whispers of Bedlam Asylum, has a very prominent female character. :)
I also bring up deviation because my current work in progress is causing me to deviate in a different way. Although I am still following my outline, I find that I am adding several chapters to flush out some situations and emotions than I had anticipated. I am not at all unhappy with the results, but I do worry that when I go back to edit that the flow might wander a bit with the unintended stuff.
No way to be sure until I'm done with the first draft. :) Guess I should get back to it.