View it this way: There are people that kill other people and ones that don't. Instead of creating both types and then torturing the bad one, only create the one that doesn't kill!
Interestingly, you've pinpointed the exact meaning of "the knowledge of good and evil". It goes something like - I know how I can be hurt, therefore I know how to hurt you.
And if I know how to hurt you(and I'm afraid of being hurt myself), I can use that knowledge to exert power over you. Keep in mind there are worse fates(by far) than death.
So you're asking for a world of beings that are incapable of murder, torture, slavery or inflicting any pain on another - So like a world with only trees and shrubs? That's good?
