This statement deserves a standing ovation! 
Understanding scripture is what I try to do as well.
“At this stage of your life” you look mentally quite fit!
So let us seek to understand what your concept “sin as an attribute of our nature” might mean.
From what you say I infer the following:
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Even if Adam had not sinned and generations had passed before the arrival of the first sin in human history, this sin would have had consequences “as an attribute of our nature” as well, just as if it had been the sin of Adam.
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After the first transgression in human history “we are all sinners” in the sense that we all share in a sinful condition, but NOT as if we had “knowingly and intentionally” sinned. In particular, and most important, this “sinful condition” of its own does not entail eternal damnation in case of death.
First of all, I would be thankful to know whether these two points correctly interpret your concept of “sin as an attribute of our nature”.
Secondly , I feel that these two points may be tightly related to @MOls idea of Original Sin:
Therefore, I would be thankful if Michelle could comment as well.