Looking to expand the bottom half? This should help with the subject of width, this is the LoRA for you. If you're looking for "depth" use this in addition to the ass slider.

I recommend playing around with the slider until you find the setting you're looking for.

(If you're going to do a Hi-Res fix, I recommend removing this LoRA and other LoRAs by me on the second go around. They won't mess with the outcome if you keep them, but I find it doesn't really add much by keeping it and you might save a couple buzz by removing it.)