The point made by @smooth is not factored in to your analysis: concentrating SP rewards large accounts more than network effects diminish them presently.
An essential - and existential - problem is that stake-weighting forces all value other than financial to zero, both on Steemit and in the real world. It is necessary to measure and weight other values to effect rational society. Simply attending to finance alone creates a society of bots that have no other purpose.
People have other values, and many of those values are far more important than money.