You could do the lessons in any order, but as you mentioned the review would not work well. (The review is one of the strengths of the program. ) You do not have to use timelines or maps. They say they want to teach Joseph, David, and Daniel ... as sort of "pegs" so they do it out of order. Their timeline does help to correct that.
There are a few memory verses that are a part of the Bible drill but not memory verses as you normally think of them.
HTH!