Hemming would be the last thing to be fixed.
The crotch length of the slacks are too short and this is giving her a wedgie. Once this was adjusted, then I would adjust width across the hips. Immediately the pantie line, the wrinkles on the hips, back and thighs would disappear. Finally, I would adjust the hem to about the the length they are in the photo. The hem appears to be just skimming the top of her shoe.
The coat is too tight across the hips and therefore causing it to bunch and form wrinkles across the back. A gusset under the sleeves and kick pleats in the back would allow the jacket to lie more smoothly when raising the arms as she is doing in this photo.
Finally, the collar:
Is the collar supposed to be up or down? Make a decision and keep it that way.
For all that we have a good time with her tasteless disasters, she really is not an unattractive woman and even has some enviable features--her height, her nice smile (when she doesn't duck her head and scowl from under her eyebrows) and other things.
I think I could dress her a lot better than she does, and make her take better advantage of her assets.
But, I'd have to insist that she practice walking and standing for the camera.