Subject is cute and lighting is fine, but her face is nearly dead center in every shot with too much empty space around her.
Try the rule of thirds as a starting point. Divide the frame in thirds, vertically and horizontally. The four lines will intersect at four points about 1/3 of the way in from the edges. Those four points are the third "nodes".
In a head and shoulders shot, or extreme close up put the subject's eye line near the upper third line, not the center. In an extreme closeup you'll need to crop the top of the head off to move the eyes up, but it will look better than if the top of the head is showing and the eyes are dead center.
For full body shots like these you still want to keep the eye line in the upper 1/3 between the upper two third nodes whether it is a vertical or horizontal format. If you angle the torso and put the main center of interest, the face, near one of the node points it gives the eye an interesting angled path to the face.
Keeping the important parts of the photo such as the face within the invisible inner boundry created by the third nodes creates a good balance between the subject and negative space surrounding it. When eye catching objects in the photo fall outside the third nodes near the edge of the frame there is a risk they will lead the eye away from your center of interest right out the eges of the photo.
The rule of thirds is ideal for every situation, but it works well when you have one strong center of interest such as the face you want to lead the eye to and keep it there. In these photos the bright dress competes with her face, so you'd want to compose it and her arms and torso in a way that the eye is lead up or over the dress to the face, not down away from it.
Chuck Gardner
This is my first photo session USM only. Comments most welcome bad
or good. Mario