I twittered recently about how at first writers often give their full attention to one plotline alone. Subsequent rewrites, we are able to multitask.
The plot line that first comes to a writer generally reflects the writer's strength and preference.
This particular writer gives great thought to the action plot line -- outer plot -- and to the romantic plot line -- romance plot (not necessary in every book, though this particular writer is a romance writer, so... Also, because romance fiction is selling well despite the economic downturn, seems to make sense to include some romance??)
Same writer struggles with the character plot line -- inner plot. She balks at filling out the character profile as it applies to the character traits and has done little to explore the protagonist's inner life. Thus, the character shows no transformation in the end. The writer especially resists coming up a flaw -- "I've never been any good at that."
Quick assessment of the key scenes:
2) End of the Beginning
3) Halfway point
The scenes themselves point to the character flaw.
As soon as we know the flaw, it is possible to determine how to rewrite each of the key scenes (and all the other ones, too), at least in relationship to the inner plot -- the character emotional development plot line.
Introduce the flaw
Deepen the readers' understanding all the different ways the flaw is revealed. Expand upon all the ways her basic flaw sabotages her from achieving her long-term goals. Yes, the Middle (1/2) is the territory of the antagonists and of the exotic or unusual world, but both of those elements serve to underline the flaw in no uncertain terms. Antagonists serve to challenge the protagonist, but generally speaking our inner issues and beliefs directly influence the growth and development of the flaw and that flaw does more to sabotage us than any external source. (Can't help it, the plot work I do gives me valuable insight into not only character's behavior but our behavior as writers, as well.)
**End (1/4): Shows the character becoming conscious of flaw and the steps she take to remake herself = character transformation.