[S I M T A N]

I'm not sure what you mean by evil. To you, a child stealing a lollipop is the same as a mass murderer.

Haven't you heard of "yawm al akhirah", aka judgment day? That's when we all get to see those who choose to do evil face justice. 

We are told to expect tests here on earth, of various kinds, as explained in the Quran 2:155. These may cause us to suffer. For those who are patient, a great reward is promised. So there, a simple answer to your great 'evil and suffering' question. If we want to see the picture, it is now showing in Palestine. One side doing great evil and another side is going through great suffering. Evil and suffering.

The reason why you fail to see the 'oneness' of sin is because you operate with a totally different value system from that of the God of the Scripture. In God's economy, sin is not measured in terms of severity, in the way your faith sets down. Any sin, however slight or however heinous, is a privation of obedience, a lawlessness, and the penalty for 'unredeemed' sin is death.