I'd like to see more TNG to STO-era generic civilian colonies, including orbital trading / maintenance stations. Farms surrounded by self-defense measures, apartment buildings, motor pools, etc.
In example: decommissioned / "re-purposed" Utopia Planetia parking stations with a marina-style network of external docking arms with walkways / look-out points running out to freighters, extremely-low warp/impulse-capable houseboats, etc.
Federation underwater colonies?
I'd like to see more (warp capable) freighters.