A Fire Upon the Deep
If Clarke's Overlords left you aching for cosmic hierarchies where humanity isn't the apex, here's a universe stratified by physics itself—intelligence rises and falls with galactic geography, rendering godhood and extinction mere matters of location. Transcendence isn't metaphor but mathematical inevitability, and ancient malevolence awakens to devour minds ascending past their ceiling, delivering the same melancholic vertigo you craved when the children merged and left Earth behind.