you probably missed these verses 19:62; 21:101-103; 56:25. That verse describes a "scene". It doesn't mean it's recurring.
Even so, it's a scene you ought to remember for the rest of your "peaceful" eternity which you share with a being who tortures other people. You seem like a cruel SOB though, so maybe it wouldn't trouble you.
It's not about Him knowing best, it's about Him doing whatever He wants with what He created.
Assuming there were no god, do you think it's alright for parents to mutilate and torture their children? They created them, after all.
No, man could have been like the rest of the universe, without an ability to choose but to obey God. This ability was a gift with heavy responsibility, which man accepted.
Who is this "man" you are talking of? Sure as hell wasn't me. I don't share ego with other men.
True, but again, God simply does whatever He chooses... and He chose to create us.
You project your human concept of mercy on God. God is NOT human. When God doesn't care about me, He doesn't care to give me anything less than the worst imaginable condition: an eternity in Hell.
Allah knew what human words refer to. Didn't Allah refer to himself as all-merciful? He knew what we understand by that word, and chose to employ it.
PS: why do you believe Qur'an is revealed word of god?