the primary sin is not recognising what is sin. someone convinced eve to eat a fruit saying it would have magical effects on her, and she seduced adam into joining her. it was not their property. so, fraud, then theft, then fraud, then more theft. you can't say that they didn't know it was someone else's tree and they specifically asked them not to eat it.
cain was jealous of abel because the Lord liked his bbq and didn't like abel's vegan salad. that pattern repeats with jacob (later israel) and his brother esau, and again the same pattern, envy and pride leading to - in this case, conspiracy to murder.
adam and eve were not as evil as cain or esau.
also, abraham destroyed his father's idols and left the biggest one standing and said "it was him, they have power, right? right?"
this "all have sinned" is not the same as "all are evil". adam was not evil, eve was naive, but cain was evil, esau was evil (and he kept on down that path until his end as well).
the two takeaways i get from this are that women are easy to bamboozle and envious brothers are a plague.
further, repeatedly, even in genesis and then througout the rest of the book there is promised a time when evil would no longer control the fate of humanity. so, it's not even stated that sin is unrequitable. it is, and it will be quitted.
i agree with your points for the most part but i deny that we cannot live free of the baleful influence of proud, envious, duplicitous people. you can just walk away from them. if they hunt you, then you are perfectly justified in ending them. for the most part it's not that difficult to get that far away, even on foot it's possible in a few weeks to be so far from someone that you never see them again.
also, regarding the "tower" of babel i always point to the "skyscraper index" - building majestic tall buildings tends to be a mark of a stage of the debasement of money, and society, where its own corruption destroys it, if nothing else also comes to help out, like a solar flare or meteor.
