I have to say this sigmoid function is 'fascinating' me as it could avoid the disadvantages of the linear and the quadratic curve. Therefore I wanted to attract some attention for this idea and see if some other steemians might be interested, too. :)
Of course the exact implementation is what finally would matter, but before to rack my brain too much, I wanted to plumb if the idea is able to attract some interest.
Anyway: thanks for drawing the attention on diminishing returns again!