Hi Jeff,
The Review area is not meaning a lot any more, because most of the Review information is in the check marks for correct, given and incorrect answers. It is seldom used. I would not remove it.
If you want to remove something from question slides, don't delete them but uncheck in the Options accordion of the Quiz Properties panel.
Buttons on question slides are embedded in the question slides, they do not have a separate timeline. Same for the captions like Type of Question, Question, Answers. Do not delete them or you could cause a lot of problems. For that same reason you cannot just copy/paste those embedded objects at all. If you want to change the properties, the location, size, you can use the Quiz master slides and or the object styles for quizzing objects.
Lilybiri