A possible problem with getting rid of religious influence is that doing so removes a huge chunck of native culture. Chip away at a nation's culture and you end up with anonymity. I don't feel that's a good thing. Frankly, I see little virtue in melting pots.
Insofar as Christianity goes, its Ten Golden Rules are pretty damned good, offend no-one and are very much biased towards an easy interrelationship of folks from different cultural heritages. They are primarily about respect for one another.
I am not saying that it is a bad thing to avoid killing thy neighbor. I am saying that avoiding doing it because God told you so, or because your priest told you that God told you so, or because the laws of the country says that God says so has some consequences that I am sceptical about.
Western thinking is heavily influenced by Christianity (and Christianity was heavily influenced by other religions and philosophers), but I prefer being able to discard parts of the religion at will.