Is Moral pluralism preferable to a common morality?

In today's world we are living in an age arguably of greater moral pluralism than ever before. Is this state of affairs preferable to a previous age not so long ago where Christian morality was the dominant morality followed by the majority of the population. But for the first time in 1,500 years it has become a minority religion in the West. In the marketplace of values today the individual can pick and choose their own values where Christianity is now just one among many other stalls.
In the Hellenistic period of the Ancient Graeco Roman world there were also many competing Philosophical schools, such as Stoicism, Epicureanism, Platonism, and others who each set out their own stalls. This was also a cosmopolitan period, a time of upheaval, change, and the intermixing of cultures and traditions like our own. Can this lead to a healthier growth of tolerance, cross cultural understanding and openness?