It would have been more peaceful than the present condition. Just for a second close your eyes and let your mind ponder for a minute about all the aspects that the world would have reaped without religions.
No wars in the name of religion, no communal riots over petty issues, no discrimination, no human genocides in name of religion and lots more....
But why do we have a religion? Many people relate it to spirituality. If you are religious then you are spiritual. I laugh at such things and don't argue with that person. As far as I know, ancient people worshiped nature and that's well fine with me. But slowly it shifted towards non-existent mythological characters which were just heard but not seen. People started believing in legends as we find some kind of calm and peace in mind when we hear the victory of good over evil and we start believing in them blindingly about the so called super powers the person possesses and we start considering him God. This belief forms the base of every religion. It's fine till here. It's obvious that we start believing in someone in time of despair. Now here part-2.
The world has many religions. Here starts exploitation in the name of religion. People start telling and preaching each other how my religion is greater than others and do the job of pouring oil in the fire. This ignites the mind of the person who is hearing this and he too spreads the word to others. These preachers become silent spectators when the fire takes a violent face. Why do they do this? Simple reason- personal gain and greed. They feel delighted when someone's else blood is spilling at their own expense. They see their aim getting full filled and these leads to mistrust among different people in the world. We are held at ransom due to greediness of few people in this world.
In my opinion the world would have been a better place without such elements but they come with religion. Just like buy 2 soap bars and get one free! Just for a moment what all wrong deeds we have done in the name of religion from since religion came into existence. Atheist groups advocate all these facts and advocate many campaigns like why to fear over your deeds with religion.
Though issues go well past the discussions about the need of religion in the present world. I have seen in today's world that the belief in one's own religion is getting stronger day by day compounding more problems than ever instead of solving them. One day will come when we will realize our mistakes that we have done in the name of religion but by that time it will be too late.....
(This post just expresses only one point of view)