If something looks like it is taking over, you need to pare back its importance, but still have it make sense.
Keep in mind that your invocation of place is ultimately to serve the characters and story within it. As a storyteller, you need think about how much complexity you want to show; never forget that all of this is to support the story, not be the story.
Despite the prevalence of the post-apocalyptic approach, remember that you also have the option to portray the actual details of the global catastrophe as it happens, as well as the series of events leading up to it.
A society that fails to deliver on these to all people will become unstable until the will to restore delivery of these needs across the society though seldom equally is regained; There are tipping points to human tolerance of what they are prepared to put up with before acting.
Many online resources, such as this list from the Science Fiction and Fantasy Writers of America websitecontain suggested questions about everything from social organisation and government to the rules of magic and technology.
Start with the basics: How do people live here? Where reality and fantasy collide An interesting way to provide contrast or conflict within your story is by developing your fictional world alongside, or within, an established location — for example, right here on Earth.