I think I'd like to see what people would do in their leisure time or domestic work . You see so many stories about travel and war, but you rarely see people interact outside of that. And if you do, it's usually not made unique for a setting that isn't Earth.
What cutlery do they use? What does a morning routine look like? In a world where fire magic is commonplace, how do they cook? How would those things evolve over centuries?
Fantasy especially feels stagnant for this, but I think sci-fi is guilty of this too. Are there things in specific works where an innocuous detail made you wonder more about how a setting worked?
Unjust Depths does a lot of this mundane details of life stuff in service of showing the difference between the communist and imperialist societies.
One thing I could ask for is that any author who's showing orbital mechanics at least play a little KSP first.