I haven't read any replies so I apologise if this reply is a repeat of an earlier reply..
I don't think evil has to exist for good to exist...
I don't think freewill has to lead to evil...
good and evil needs to be defined and a standard needs to be set to measure them..
If you believe in God some standards are set, if you don't those standards are relative...
What is God's standard then? Please summarise for us.