Great subject.
I interpret the fall somewhat differently. God gave Adam and Eve all the facts: eat from the tree and you will die. The sin was disobedience on one level, but on another, it was a lack of faith. The serpent lied to them, saying they wouldn't die. It's also relevant that God commanded the Tree of Life to be hidden, lest they eat from it and live. Here, two points emerge: first, if God did not enforce death, He would be contradicting His word, making Him a liar. Secondly, it would have been a minor act for God to show mercy and allow them to live by eating from the other tree. However, given the nature of the crime, it was clearly not in mankind's best interests to be forgiven at that time.
But why all this pretense, right? God is all-powerful—just intervene! Kill the snake or at least warn them.
The issue is interconnectedness. People say, "Well, you have free will." But you have free will because God has free will. Yet, if God is morally perfect, why not make us morally perfect too? (ignoring, for the moment, that this is literally the goal of creation for mankind)
The way I see it, the very act of creation, from God's perspective, requires that He withdraw. If He did not withdraw, there would only be Him. Yet without God, everything would eventually perish. Withdrawn or not, He sustains it all. So, why create anything? The answer is love. Love requires an object. But why does God love evil beings, as we are?
He doesn't love us "as we are." He loves us through Christ. Before Christ—or rather, before someone's knowledge of Christ—He loved us on credit. After Christ, He loved us on debit. (I borrowed this phrase from a Shai Linne song:
https://www.youtube.com/watch?v=16uIROrctLE)
This is why the death and resurrection of Jesus Christ are at the nucleus of reality. It is a profound miracle. All the signs and wonders performed were really to address our lack of faith ("if you don't believe me, at least believe the works"). The real miracle was Christ's existence.
Was Jesus God? If that's the case, then it's all a strange spectacle. Jesus said He wasn't God, that God was greater, and that only God was good. But He also declared, "Before Abraham was, I AM." Talk about confusing.
God is like us in that He is not God. He is like God in that He was morally perfect and obedient in God's eyes. Did Christ get angry, was He scared, did He eat with dirty hands, was He disrespectful to authority? Yes. But these are human notions of good.
I could go on, but the suffering, hell, death...these are all things that will be destroyed. So, what we are really asking is, why MUST we go through this? But just like children whose parents tell them, "When you're older, you'll understand," it is true that as you grow in faith and knowledge of God, these things make more sense.
I will say that in my learning, I believe the primary reason modern believers struggle with this, is that hell and the resurrections (yes, plural) are not properly understood. There is general confusion about "when" hell occurs in relation to the resurrection, and there is also confusion about whether non-Christians will be resurrected. This poor teaching has exacerbated the false teaching that God is unjust, and has led to weird mental gymnastics where God "is just because He is God, even when He does evil, and we're just too dumb to understand". But God is not the God of confusion (1 Cor 14:33)