Hi @Frédéric5EE2 ,
The rule of third is not a hard and fast rule. There are a few points of focus in the view of your camera (about 11). Once you utilize these correctly you'll get nice images. You may do some of your images using the rule of third, however having too much negative space is not essential for stock. For single subject, the larger it is, the better, but leave space around the subject to facilitate cropping. Also I do not understand why you could not avoid cropping the hand of the first model. There is a pose for a picture, capture it in its entirety.
Best wishes
JG
Photographer and Nutrition Author