I like it, there is a lot of drama in this picture - helped by your fluid proportions.
Here I disagree with moebean, van Gogh's anatomy wouldn't always withstand criticism, but it did add drama - take a look at The sower with sickle
Two changes I would consider are 1) to introduce a little more shadow around her left knee* - on the inside of her thigh, her shin, and waist. This will throw the knee forward and add drama, and 2) add a little shade to the left of the central cloud, to reinforce the suggestion that the sun is to the top right of the picture, and to send the cloud back behind the picture. Neither change is essential, and if attempted, should be subtle.
*The foreshortened knee on the right of the picture