I've always wondered how much of Preservation actually went into the humans of Scadrial. And if more people means weaker Preservation, and if so, how many people would there need to have been born on scadrial before this became a problem.
Additionally, what happens to that part of Preservation that went into humans when they die. Does it go to the beyond with them? Does this mean that Preservation is being eroded away forever? And if in may eons of people being born, will there be no longer any Preservation left and the people being born will be mindless/souless/what-have-you?