Didn't Dante say something or other about Virtuous non-believers simply going to a calm plain when they die?

To be honest it's not where you go at the end of life, its the journey through life that matters. You don't need religion to have morals. Socrates, Plato, and Aristotle didn't have a religion persay, just a philosophy on how to live. All you need is reason and intelligence.

So whether there is or isn't an afterlife, I'm still going to uphold those virtues (or at least try), not because a doctrine says I should, but because I want to. I know some people won't do the same, but who cares otherwise.

If that's the case, then I don't have to worry about believing in the wrong religion.

I think if Catholicism, Protestantism and all other Christian denominations and sub-movements are added together, they dwarf the population of any other faith by a margin of at least a billion odd.