I will get back to issues 2-5, but to answer the question above, I think it is misconstructed.
“Given the nature of God” must mean given that God is omnipotent, omniscient and omnibenevolent or he wouldn’t be the proper object of worship.
If he has those qualities, then acting in unexpected ways and commanding unexpected (to us) commands would come with the territory, so to speak. We couldn’t know the right course of action in every case because we are not omniscient nor omnibenevolent. God’s judgments would not always correspond with ours because of our limitations.
If God were to determine that some of us were unworthy to go on living because he knows all and is all-loving, then on what grounds could we possibly argue otherwise and make a better judgement than one made by the all-knowing, all-good God?
If you, falsely, arrive at a notion about the “nature of God” by ONLY reading the problematic passages in the Bible, then it is this notion that is skewed. If you read the Bible as a whole, it is an entirely different conception of the “nature of God” that comes about.
Consider issue 2) Abraham sacrificing Isaac. The intent of the passage is to point out that Abraham loved Isaac, his beloved son, profoundly and yet would place Isaac’s fate into God’s hands. This was to foreshadow God’s act of placing his Son, Jesus, into the hands of human beings to determine his fate. Now Abraham knew God intimately, which is why God could “stay his hand” and Abraham would listen. Human beings entrusted with the fate of Jesus did not know God and so their hands were not “stayed.” It took greater “faith” for God to entrust Jesus into human hands than it did for Abraham to entrust Isaac into God’s hands. Humans are notoriously fickle, irresponsible and untrustworthy. God is quite the opposite once you get to know him. Humans “sacrificed” Jesus, determining his fate, and God did not interfere because he followed through with his “act of faith” in humanity, no matter what the cost. He was and is “all in” in his part of the covenant with humanity.
God did not need to demonstrate his power to Abraham because Abraham knew him, trusted him and listened to him. Abraham knew that God has power over life and over death, so that even if he did as God commanded and sacrificed Isaac, God would make all things right in the end. However, God had to demonstrate his power to humanity by raising Jesus from the dead after human beings refused to recognize, listen to or trust his Word.
The point is that God has power over life and death - power over the lives and deaths of the Amalekites, the Jews, Abraham and Isaac, all of us. The question is whether we trust that he does. By resurrecting Jesus, he showed that power. By ordering the deaths of the Amalekites he was showing that power - it is by his authority we live and his authority we die because all that exists exists because of him.
That is the “nature of God” that is the point being made. Do we give God “his due,” or do we constantly second guess and assert our dominance and power over him like those who crucified Jesus did?
The Word became flesh, but do we receive him? Isaac was not sacrificed because God himself would provide the lamb for sacrifice, his Son, Jesus - the “all in” stake that would eternally bind him to us, unconditionally.
Do you understand why animals were sacrificed in the Old Testament? It was a symbol of covenant between families or groups. The animal was cut in half as a symbol that breaking the agreement was like cutting in half the newly formed unity - the body of the two parties who had come together in covenant. It was an unconditional unification of the two who became one - breaking the covenant was tantamount to killing both parties - symbolized by splitting the animal in half, thus killing it.
By the way, Abraham knew he had broken trust with God, so he was following through with killing Isaac because, by breaking trust - breaking his covenant with God (a long story) - the right thing to do was sacrifice Isaac because he no longer deserved to be called Isaac’s father and was giving Isaac back to God who gifted Isaac to him. God “staying his hand” was God’s answer to Abraham that Abraham was forgiven and the covenant restored by Abraham’s willingness and faith.
We don’t get this because we don’t understand the passionate faith of Abraham.
Also, parents are constantly giving their children to God in many ways - when through disease, accident or tragedy God “takes” them back, but also through the choices their children make which parents must take a “hands off” approach and not try to control the outcome. If we live dispassionately, this seems not much of a sacrifice, but passionate love for one’s children will often be very like Abraham’s sacrifice when we have to carry out a decision or abstain from having our way because that is God’s will.
There is far more going on in the Bible story and “nature of God” than we realize by isolating problematic texts.