I don't think that would hold true. A lot of narcissists may just feel themselves superior and need no divine reason for that. Narcissism is usually just a coverup for an actual bad self-esteem, a reactive psychological defense to having their sense of self-worth attacked a great deal during childhood, often combined with being raised by parents that try to bring them up with a belief that they are somehow special. Nothing about this requires religion. I'm not sure psychopathy, where the person really believes they ARE God and the world revolves around them even necessarily needs religion, even if it kind of is one.
I do know lots of folks like this. Who pretty much aren't agnostic or atheist but just really don't care enough to wonder. That seems to be the default really. Most of them though do declare a religion, whatever they were told by their parents generally works for them because they don't give a damn.
You do not need a religion to be a believer, if you form your worldview based on the belief that you youreself is special, then you are a believer.
The only atheist religion I know of is the LaVeyan satanism, most atheist does not have a religion.
Most people in the west are disqualified as non-believers as they believe in the free market theories in the same way a religious person believes in the religions scriptures. They believe that technological progress is impossible without a free market, that infinite economical growth is a possibility and the most important thing to achieve in this life, that we must waste money (consume as much as possible) to stay wealthy, that high personal depth is the best sign of a healthy society, that there exist no alternatives, that every activity is more efficiently performed if it is privatized, that work is the goal and consumption is the way to achieve it instead of the other way around.
They often have a hard time understanding how economical growth on the paper/statistic can be an economical decline in reality when all the consequences of the activities that caused said growth has been taken into account; because it is often impossible to quantify into statistics/money the consequences that does not fit into any economical models, like ecological consequences. An economical good toady may result in an even bigger economical bad later. Short term trumps long term in the common economical theories.
Look at how today all politicians keep nagging about how people need to work more, consume more, and most folks agree even though the only solution to global warming is to work less, consume less, lower our living standard.
But people believe so strongly that economical growth and technological progress that said growth promises us will solve the climate problem without us sacrificing one inch of our living standard.
Look at how Obama was revered (especially during the election campaign), by a lot of Americans and Europeans as something close to a new messiah, all because the common believer desperately craved a modern time Saviour of some kind.
He even got the nobel peace price half a year into his presidency (oct. 2009) mainly because he signed the Russian proposed nuclear nonproliferation agreement that George W. Bush refused to sign. There were other reasons cited, but they are all imo very thin in essence. Only true believers can use arguments like "he is not bush", "He agreed with the Russians proposal", "he is going to change the world", or "his skin color makes him special" to decide who deserves a historically revered peace price that is supposed to elevate true historical champions of peace and betterment. Then the next peace price was given to a trade league by the name of EU, citing that all the wars that didn't happen in Europe after world war two was prevented by EU, hogwash, European countries was so war weary at that point that peace would have reigned the continent even without a trade league, and the up and coming economical globalization would have made the countries financially dependent on each other without the existence of EU anyhow.
Look at how Americans today insist that the USA is a banana republic in a strange attempt to rationalize the fact that a moron got elected as president. "Adds on facebook made me vote against my own political conviction", any country could have done the same and I'm sure that if the adds had been made by an scandinavian science project there would have been no allegation about Trump colluding with scandinavians to win the election.
This naturally takes us over to the strong belief a lot of folk in the west have about Russia, "Russia is bent on world domination", "Russians are evil", "Putin is aware of, personally responsible, and control everything done by any Russians or Russian speaking persons in the world", "Russia can at any moment invade the baltic countries or scandinavia even though Russias defense budget is about the same as that of England which again equals 7% of NATO's military budget.
Jens Stoltenberg (current head of NATO) is currently traveling from one NATO country to another advocating rearmament, a new arms race, and the Russian threat is his selling point.
Wow, I'm ranting again.... Sorry
Back to point, the way current religions are designed in C2C, there is imo little place for atheisms and agnosticism inside that system.
Organizations based on the
Humanism movement can have a place among C2C religions, they have buildings dedicated to spreading their belief and for holding ceremonies like non-religious funeral wakes, weddings etc.
If you (TB) were to change the religion system through the ideas property you have planned, then I guess agnosticism and atheism would fit better in that system alongside other ideas like religions.