> Evil exists in order that we have free will, which necessarily includes the freedom to do evil.

This is a total cop-out: A lot of suffering is caused by circumstances beyond the control of any one individual, or even group. If God allows suffering caused by no human, he cannot truly be considered good.

To exemplify, Mount Vesuvius explodes and all the inhabitants of Pompeii are killed. God could have whisked them off to safety, but chose not to. If free will was a concern to him, he could have asked them first if they wanted to die there, or preferred to be moved to safety. He did not.