Apparently we share the same view regarding the stage in which “Adam and Eve” were created: Evolutionary selfishness was not an ingredient in the temptation which led to their Fall (the first sin of human history).
However history and daily evidence show that evolutionary selfish tendencies contribute a lot to the temptations humans undergo: In this respect David’s “concupiscence” is paramount. So I conclude that after the Fall “Adam and Eve” lost the perfect control of the evolutionary selfish tendencies, and also each new human person comes into existence with this “lack of control” and the resulting “propensity to sin”. This is an important ingredient of the so called “stage of original sin”, which at the end of the day is a “stage of being in need of Redemption”.
I would be thankful to know whether you agree to this view as well.
In any case, as you very well say, “God provided a means of Redemption” for the first sin in human history (the sin of “Adam and Eve”) and all the subsequent sins humans do. Part of this “means” is that God has bound everyone over to “the stage of original sin” so that “He may have mercy on them all” (Romans 11:32), as David’s story and his Psalm 51 magnificently demonstrate.