Much of the middle east: Islam. Much of South America and Central Africa: Catholicism.
Taking it a bit further, look at the best places to live, and I think it likely you will find that NO religion holds all that much sway in the culture.
I will betcha that holds true for "the best places to live."
I think Islam is big in South Africa, but I never saw much anyone care about or show any interest in religion down there. I am certain the churches were all packed on Sundays, of course. Maybe that's a social thing.
So you are correct. It's not the PRESENCE of religion/religions, but the degree of SERIOUSNESS that they are taken. One of the more glaring examples of this is when the Muslim objects to being told he's in a violent belief set, he says "But your old Testament says kill, kill, kill" and we answer "Yeah, but we don't pay any attention to that, dude."
Some things like that are hard to comprehend. Why and how can something be believed, but not that seriously.
Yeah, that's a more comprehensive way to state it, and looking at my own life, I would have to agree. I was raised very Christian, and even though the religion overtly speaks of tolerance, they simultaneously taught us to be aloof, superior, distrustful of all people (especially successful people and other sects of christianity), and generally rotten 'values'. Yet the culture in the US is rather secular. There are no serious penalties, in the sense that there are in places ruled by religious law, to questioning the unquestionable answers presented by religion. Personal, yes. It's not easy to wake up from a dream that was forced upon you since birth. It's not easy to deal with the fallout when you do, up to and including family members who will no longer speak to you.
But the culture allows it to happen, and in places that are increasingly irreligious, the quality of life seems to be improving across the board. Sweden comes to mind. I can't speak to that one directly, having never been there, but I have lived in more secular AND more religious areas of the United States, and the places with a heavy religious influence, the quality of life is very good for the well connected, and not so great for anyone else. But again, the consequences are more personal than not, and can be overcome. When a religion actually rules a culture, all the bad parts of their scripture come quickly to the fore.