My main point in a C&C on these is that the best way to emphasize the model and the product is to get the background out of focus and farther behind her, so that the background fabric falls well,well outside the acceptable depth of field. Ironing the muslin might be a PITA, but it will eliminate the wrinkles. However...if you can get the background fabric literally 10 to 12 feet behind her, it will be far enough behind that wrinkles are a non-factor.
THIS very issue is a real problem/factor when shooting a crop-frame d-slr in a cramped space, and I know first-hand how difficult it can be to shoot in a garage or living room makeshift studio. I in fact used to work in a portrait studio where I shot a half-frame long-roll film camera with an image capture size very similar in size to a Nikon 1.5x APS-C frame, so I am intimately familiar with backgrounds and how they render with the smaller capture format. At another studio, we used RB67's which had a MUCH shallower depth of fiend and a MUCH more impressionistic background rendering of fabric backdrops. The best thing to do with a 1.5x d-slr is to shoot from a far distance, with a telephoto lens setting,and to keep the model as far in front of the fabric as you can; the long lens will give a narrow angle of view **behind** the model, and this will sublimate the background. It's worth it to open the garage door and shoot from outside in, to get farther away, or even to shoot from another room, to get the increased camera distance.
I also see some evidence of a too-cool white balance in shots #2 and #3...she looks a tad bit blueish in her face. Also, and not many people think of this, but most real people look better when they apply a pumice stone to their elbows before a photo session. She actually looks like an excellent model for this Bad Dad line of T-shirts. Right age, right body type, right "look". Very pretty lady.