Unfortunately, big models can be a tough gig.
#1. I would advise against any shooting position where some parts of the body are closer to the camera than others, including this low position. And the wide angle/close crop only makes her fill the frame more. In particular the elbow/forearm being closer to the camera makes it appear larger. As for color, I'd like to see a more neutral white in the body of the dress, and some brightness/contrast curves could help cut the highlight problem. This can be done in RGB but preferably in Lab, where you could steepen the A/B curves to bring out more color separation in the highlights.
#2. A good idea but taller is better. More body length will decrease the appearance of width. As for exposure, I feel this is a shot that would benefit either from stronger fill flash or subject underexposure and then teasing back out the detail in post.
#3. Good exposure but a little confusing. The image doesn't speak to me.
#4. Lengthening the torso helped somewhat but the posture is awkward, making the curve of her ass/back appear more like a hump and placing too much emphasis on those giant knockers. The flat light on the face I feel is detrimental. It rounds it out too much. Lighting from the side to increase shadows will add more dimensional qualities to the face, making it appear more angular and less round and large.
All in all, for these shots with this sort of model, I would increase fill flash to deal with the background exposure problem, and light from the side (make sure it's sun-side to avoid any directional confusion). I would emphasize tall, or long posture, avoid silhouetting at all cost, and make extra sure all extremities are as equally distanced from the camera as possible.