The ending .... I woke up in the middle of the night wondering if this was the end of Jack Reacher. Yes, his stories could continue to be told, but they would technically be earlier history.
Since he had not been able to save any of the characters it seemed plausible he didn't make it.
It was also so different, and still good, without a new physical fight every other chapter. Reached was more contemplative and introspective in this novel.
Thank you Lee Child.