The PS work is adequate, but the shot has several problems. One thing is the prominence of the shadow on the wall. It is usually better to move the model away from walls to avoid this sort of distraction. The WB seems to be off also and this probably due to the yellow wall ( but perhaps the WB is really off and that is a white wall
). Pose wise, this sort of pose rarely can work because it makes the model look a little heavier. Usually you can get a slimming effect by rotating the model's upper torso more toward the camera.
Another problem is cropping. You're right that the upper arm needed to go, but then we also have a cropped off hand.
So PS OK, image not so OK.
Re: Amputation with elements