If you can get past the Christian theology - although it's extremely valid if you can't - there's a lot in this book that I think you'd really like, in particular some really neat stuff with afterlife guardians and abandoned afterlives, and some of the character dynamics, in particular one that made me think a lot of Zemo in The Falcon & the Winter Soldier. It does keep unavoidably dipping back into the Christian metaphysics, though.