Interesting but confusing (some spoilers)

I generally like post-apocalyptic dystopian fiction, and also cult and folk horror type stuff so I mostly enjoyed this. But I think there could have been better ways to reduce confusion. Like, what is the back story of the main character in relation to the cult group?

At some point you start to wonder, okay who are the good and bad guys here. It is not clear who has the good or bad motives. By the end you will doubt what you had assumed from the beginning.

I'm still not sure what I think of everything, including the very end where a big reveal happens. What are the burned zombie-like people all about? What is the significance of the driver speaking Esperanto? Is this a sign that there was an attempt before or after the rapture to unite the world?

I read the plot description on wikipedia, and that doesn't explain everything either. I'm curious about how others interpreted it.

So, there is a lot there that kept me asking questions and thinking. It's at least thought provoking, but at the time I was watching the movie I kept rewinding a minute and paying closer attention to some scenes.