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?
One thing that I wish we saw more of was how things work when they're not functioning, like what can go wrong and how, and the janky ways people go about fixing it. I remember when the first trailers for Force Awakens came out, and people were bitching about how Rey's hoverbike was a shitty design and my reaction was like: yeah. She's on a desert backwater sifting through garbage. She doesn't find a Mercedes, she finds a fucking Gremlin, and patches it together well enough to get around. I want stuff that's poorly designed or that's old and falling apart. I want antigravity packs that are clearly held together with duct tape and bondo. I want magic mirrors that flicker and shriek until you hit them just right, because there's a defect in the scrying array that lets Hell bleed into the feed. Janky cybernetic arms that are discontinued and need DIY fix-its because the parts aren't made anymore.
It makes the world feel more real. People don't go for the perfect thing, they go for what's cheap, and spend their money on booze and junk food. The Murderbot Diaries do a pretty good job of this, with Murderbot bitching about how nothing produced in the Corporate Rim really ever works right. It's great.
One of my favourite minute details about Neuromancer is exactly this. A one-off background character, a bartender, is described as having an outdated, clunky old cybernetic arm, which you don't really see in modern cyberpunk. Everyone has shiny and modern stuff, even "last gen" when it shows up is indistinguishable
I remember that. There's a character in the game Observer like that as well, with shitty low-cost prosthetics all the VA equivalent would pay for, it's implied
There's a sequence in Unjust Depths where a character spends a whole day trying to find a place that will service her prosthetic arm and all of the legitimate clinics and manufacturers send her away because it's not their product and she doesn't have insurance (and because she's a racial minority)
One of my fantasy airship characters is a dwarf who is on the airship because, among other reasons, he's dodging creditors who are after him because he never paid for the undead arm he had grafted on to replace the one he lost in a factory accident, and that's easier to do when you have no permanent address and your contract stipulates cash payouts for your share
EDIT: Worth mentioning, this factory accident killed several friends of his and was the result of burgher greed and safety skimping, it also radicalized him and I'm thinking that his other reasons are some light terrorism maybe