Omni-benevolent God would be benevolent toward evil too. Pain is inevitable, but suffering is optional, as they say. Is pain evil? And how much of it can be prevented? In my “book”, the whole world is perfect. In yours, God said that all what is created is good, or just about right. Why do you doubt it? Those are IMO more important questions. And here's a short poem to conclude my brief reply:

Well, it should be understood,
there's no evil, there's no good.
Love the Devil as your brother,
God will bless you like no other.