Her light-colored jacket is a little too predominant and kind of overwhelms the image, distracting us from her face.

Face placement in the center of the frame with so much empty space that doesn’t add to the composition adds to the above effect.

Try a different crop to get rid of some jacket, some empty space at top, and place her eye and maybe the ear near vertical 3rd intersections.

Highlights are decently exposed, but because of the contrasty light, most of her face and eyes (which is what we want to see) is dropped into dull, underexposed shadow. You really need a reflector card (just a big piece of white foam board will do) or a fill flash to bounce some light back into the shadows if you’re going to shoot portraits in direct sunlight like this.

This is a crap edit, but it gives you an idea of what can be done with different framing and what the light could look like if shot with a reflector card or fill flash: Example