I love the black and white graphic quality of this skirt, but am not sure what size to order. From past experience, skirts in XS fit me perfectly at the waist, but snug and bunch in the hips when I move. If I go up to S, the waist will be loose, but fit everywhere else and shift when I move. How much do knit skirts stretch out during subsequent wearings, and how do you all assess the correct fit of knit skirts? I appreciate your tips and suggestions!