The quality of light on and the location in all your portraits are quite good. Your exposure is a bit bright on most. Picture #4 has nearly perfect exposure. The others have either overly bright skin, and/or an even brighter hat. This all could be improved using photo adjusting software.
The tilted angle on the first image seems to not improve the relaxed feeling she has.
The second image has a nice pose, but from this angle, things bunch up and get blocked by her arms. A more profile angle might show off her costume more clearly.
In the photos with the hat, the eyes are obscured by the hat and her hair. I don know if that is part of her character or not, but I would prefer to see her eyes more. When she is behind the tree, seeing her left arm and hand would be perhaps an enhancement on a decent pose. In the last photo, her hand is block much of her costume and face. She is too centered in the frame. Placing her on the edges of the frame would make a more interesting composition. Having her turn her body, bringing her left shoulder toward camera may improve her pose.
The forth pose shows off the dress nicely. I do like the semmetry of it. Her eyes would show more of she looked higher.