I have a rather naturalistic world view, I don't believe in the supernatural, but like to entertain that thought. After Death, we are probably gone, at least our consciousness. Though I like the idea of panpsychism, that the fundamental particles themselves possess something like a proto-consciousness, or something you would call spiritual, which, in its gathering, forms our consciousness. And upon death, we become part of a more collective universal consciousness. Dunno though.
As for eternal life, I'd take it. Don't understand the people that would not like to. I mean, we can potentially evolve endlessly, ending up colonizing the galaxy and explore new worlds. I doubt you would ever get bored. Just take the last 5000 years. Do you think the people living 5000 years ago would've gotten bored seeing how the world is transforming to the highly technological world we have today? We all like to read history. But with an eternal life, you would experience all of the remaining history. And in case you want to die anyways, you can still give yourself a headshot, right? (Doubt that most of the people who claim they don't want an eternal life, would actually do it once having it).