In response to your first point, I highly recommend reading this, it addresses God's possible interactions with other people in the past. There are other books that address this from the perspective of individual cultures as well
In response to your third point. Why does omniscience contradict freewill? Why would the knowledge that someone else has about you, in any way preclude you from freedom of choice?
If I offer a dog bologna in one hand and a rock in the other, I both know what he will choose, and he is still free to choose between the two. Why would they principle not hold true when extended to men and gods?
In response to your fourth point. If God did not create Adam and Eve because of the sin that he knew they would commit, he would be effectively punishing them with death/nonexistence for something they hadn't even done (yet). They freely chose to have children in a world where they understood contained suffering (the same thing that yours and my parents did), why is God responsible for their decisions?
Perhaps we are the only intelligent beings in the entire universe. Perhaps God cares because we are made in his image. Perhaps he is a God of love and can't help but care about his creation. And if for this question we are assuming God exists, he made humans to exist eternally. Eternal existence in "universe time" is still significant
Many argue that God interacted with people elsewhere, in Asia, the Americas, etc