I tried bringing out her facial features a bit more by setting a new gray point on the box behind her head. This seemed to warm the overall cast of the picture. Then I lightened it just a little using the levels settings. To bring out even more detail, I tried using a fill flash setting. When I used the fill flash I was able to bring out the house in the background.
I tried cropping the photo to eliminate the branch shadows on her sweater and didn't like the result. The overall charm of the photo is the way her hands are positioned so I left it alone.
The software I used for this is Photoshop Elements, which is a non-professional version of Photoshop.