I found Amy Peterson's book, Dangerous Territory, intriguing and encouraging. A lot of that has to do with how she makes few claims about what she had done to save the world, but instead she chronicles how God both saved and worked among those no one expected to be saved and then allowed her to be separated from them. Not only was she separated from them, but she was stuck in the ambiguous situation of being a missionary in a country where it was questionable whether they were actually necessary, as she seemed to be teaching rich folks English who had no interest in spiritual things.
Yet, God's work was also ambiguous - because God could have done so much more: protecting those she cared about, directing her to be wiser (and allowing her to return), causing more fruit to grow from missionary endeavors - and people to be wiser about them. Her honesty about how God has a tendency to act in ways that we don't understand concurs with how I see God presented in the Old Testament - almighty, but not so manageable (or not safe, as the Christianity Today review points out).
On a secondary note, I also appreciated the quiet focus she put on her integrating into the culture and how that was an important part of how she approached her task as a missionary (she probably wouldn't use the word calling, at least not anymore).
Christianity Today gave a very positive review of the book and was the reason that I picked it up in the first place: http://www.christianitytoday.com/ct/2017/april-web-only/most-dangerous-thing-missionary-hostile-country.html.
Although the following review is somewhat negative, as the author is disappointed with how she doesn't also include a more positive, less ambiguous side to missions, it does give another helpful perspective and overview of the book: http://englewoodreview.org/amy-peterson-dangerous-territory-feature-review/