They are stories.
God didn't know that Eve would take to a snake, because that didn't happen.
God knew that humans would depart from nature and become human.
That is what the story is about.
The sacrifice of Jesus, similarly, functions as a symbol.
It's not a literal account.
I don't believe Jesus was supposed to be sacrificed for our sins, or that anything else can be sacrificed for your sins.
Not literally, no.
A little suffering is nothing to a God, he could have simply forgiven Adam and Eve.
No, He couldn't... or, at least, if He did, an important part of the story would be missing.
The story illustrates the transition from nature to human; the awakening of the human consciousness.
This has consequences, according to the story.
The consequence is humility/responsibility: "sin".
A shark does not decide whether or not it kills and, therefore, is not responsible.
We are responsible, having departed from the food chain, so we're capable of sin.
As for the devil being the good guy, the devil is God.
Since people have an absurd tendency to label God good / bad / monster, it's easier for simple folk to understand if there is a good God and a bad God.
In reality, God is neither good nor bad.
The universe doesn't revolve around us.
Cosmic justice doesn't behave according to modern, Western laws.
God cannot be judged like a man, because He is not a man.
And we are not the center of the universe.
If it gets to a point that our species is too much of a threat to other species and "God kills all of us", is he a monster?
We know that individuals die and species become extinct. This is part of the balance.
We don't call God a monster, because of this... only when it applies to us.
How dare he kill a bunch of humans?
That's inexcusable, right?
But people die and naturally that leaves us with questions about our creator.
The logical answer to these questions is not "He's a monster."
That's childish and silly.