As an atheistic Jew who also celebrates the "family bonding" variant of Christmas, it can be really hard for me to write religion well. My view on religion generally extends to "I don't believe in god, it doesn't make logical sense to me" and "I don't really care about what others believe as long as it doesn't affect me/step on me". So I'm a mostly "live and let live" personality, and so is my protagonist. He suffers for this when he encounters people who most definitely do not think like that.

But history has a long accounting of religions, even people of the same religion but with subtle variances in belief, going absolutely nuts about converting or killing each other over these differences. Of people believing so ferverently in their deity that they'd actually die for it. The concept is absolutely alien to me.

That's made it incredibly difficult for me to include religion in my story. I've had to actually seek out historical accounts of religious clashes to convince myself my characters don't sound completely crazy and unrelatable for the strength of their beliefs. I oftentimes read these real life accounts and scratch my head in disbelief. But because of my own views on religion, it is really hard to write religion without is being satirical, mocking, or campy. It's taken a lot of research to shape my religions and the range of followers. Certainly did not come naturally to me, and probably explains. Why my gods are ultimately ascended humans (except for one) and not truly divine beings (and that one exception is a tree, which means it lacks the fickle politics of an anthromorphic god).

My world has only white people, but that doesn't prevent there from being racism, marginalization, and fates based on the most minute of differences. But my world is also a complex mix of real life ecology and geography that only exists above a latitude of 40 degrees, so dark skinned people wouldn't make a huge lot of sense anyway...