Sliding Scale of Shiny Versus Gritty: In general, the Empire and the Photonic Network hit shiny the hardest of anything, in the former’s case for ideological reasons combined with the fact that decaying things just drive them nuts. Everything is shiny, polished, gleaming, and in perfect working order… including the utility tunnels.
The Voniensans are shiny and polished – at least in the bits they let people see – but in more of a plasticky, ST:TNG way, since they’re less willing to let the high technologies right off the leash. The other Great Powers work on keeping up with these two, and then things get progressively grittier as you move down through lesser powers’ core words (with some situational exceptions – the Free Eilish Confederacy is stinkin’ rich and doesn’t mind showing it, for example), down through poorer colonies, until you end up in underfunded Cult Colonies and Wretched Hives like Nepscia. These latter examples can get pretty damn gritty.