Contest holder asked for contrast like tree with leafs on one side and without on the other and the trunk on the spine.
I believed it loses effect and does not catch the eye of the public. You don’t see the difference unless you to turn the book, and in order to show this, people must first be attracted to take her book at hand. Furthermore if she would distribute her book in e-reader format, the idea is completely lost.
This is why I have placed the tree a bit out of center, and show the effect of a part naked tree on the front cover.
I also have tried to visualize wind. Not only the leaves of the tree are blown away, but also the skirt of the girl indicates the presence of wind. The element wind is often used as symbol of changes to come.
I also took the liberty to vaguely show a written letter behind the clouds. Since her book is story about the life of a girl over a long period of time, a written letter takes the viewer back in time and tells a story.