bascule,
Bye-in-large this was a well written treatment. I especially liked the concept of 'sheltering', but nonetheless it contains what I think are some important misconceptions.
If extropic precursors had not developed, the universe would not have supported biological life. On one hand sub-atomic particles had to readily form relatively stable, extropic H and HE atoms and early stars had to be able to manufacture heavier elements. On another hand the slight instabilities (valences, ect) in elements where necessary if elements where to develop into the precursors of biological life. There seems to be a pattern of extropy taking two steps forward and one back.
Your treatment seems to ignore that biological life is itself a result of an 'ongoing, staged process' that generally leads to increased extropy, but an extropy whose slight entropic tendencies permit the development of the next stage of increased complexity.
aguy2