Watch for how shadows are cast, as here with the shadow from her arm across her shirt. Since this appears to be a posed shot, you should have ironed her shirt, and there even appears to be a stain on her shirt.
Overall, this could be improved most by improving your lighting.
Nice composition. Good pose. IMHO, the lighting could have been a little softer to avoid the harsh shadows. Also, seems a little under-exposed and lacking contrast. Only these aspects make this image weaker.