>>713575341 (OP)There is a much simpler and better way to define soul.
It is passion. Passion is visible and senseable. A passion for what they are doing can be felt and it is this passion that amplifies the enjoyment of the work, it is a multiplier. The reverse is also true and a multiplier as well, when there is no passion everything feels mechanical, you can sense that it is merely a product designed to be sold with no greater thought behind it besides that marketing told them it will sell.
Passion can also be applied to your image. It is not the flaws and imperfections or lack thereof, it is that the left was drawn by hand because they wanted to draw a circle while the right was a circle tool because they had to put a circle there.