The OP wasn't about nonbelievers getting to heaven. It was expressing that the concept of unbelievers being tortured forever simply because of nonbelief (and especially in justified nonbelief, in lack of evidence) is cruel, malevolent, and something that a just and merciful god wouldn't do.
That is not entirely true either, you haven't grasped it yet. Although there are punishments for non-believers, but there are for some believers too, so being a believer is not as easy as you are inclined to think.
That said, if the non-believers, were some good reasonable people who are well aware of the concept of goodness( like so many people are) and they PRACTICE that goodness out of love, care for humanity, and have not yet come to know about the truth about God, due to whichever reasons, are pretty much good candidates for heaven as much as the practicing believers.
But , due to lack of practice of sound Islamic teachings, believers are as scared of Hell fire as any other person would be who believes in Hell for a just accountability. But the punishment of those people in hell will be of limited time period, and after serving their sentence ,they will be allowed in heaven, for they believed in one God.
And well, nobody is going to be tortured simply because they lacked evidence against God, whats more unjustified is the thought that a person wont even ask God for Him to bring him/her closer to the signs where they will be able to believe. God is just , so even in your's or anyone's dis-belief, He is accessible to all and encourages His people to seek for as much guidance as they want to, and its quite unfair to oneself if we don't allow ourselves to communicate with God , because that really hampers our 3rd dimension which is a spiritual dimension.
Believers meditate from their spiritual dimension as much as their physical dimension, but when a person who does not believe in a spiritual dimension, and hasn't searched for it in himself, pretty much limits his capabilities within the realms of his physical dimension which go as far as the vision goes, what about beyond? Telescopes/microscopes? well they require for you to see through the naked eye too.