'Why not construct man to be of the kind that they love their neighbor as themselves naturally?'
sin is foreign to God , as said in the bible,indeed God fixed mans sin by coming to earth and being killed in the flesh and suffering for our sin ,what more do you want ,what else would you have him do?
if it is a perfect place with no sin you seek Rhain then seek the kingdom of God.
'But the devil tempts people.
And god turns people's hearts to stone and makes them sin.'
yes evil tempts people yet God still accepts us if we believe in his name.if people truly seek God and good ways then their hearts will care more for good rather than evil.