When I was young, I remember watching a movie called The Day After. Up to this point of my life I had heard that a nuclear exchange between the USA and the USSR would surely mean the death of us all with a flash of light and one nuclear winter. The Day After showed a less completely apocalyptic view, with some hospitals still functioning and the government at least trying to establish new farming techniques post extreme radiation and EMP pulses. The movie covers the mid west so you can assume the coasts of the United States were gone and the future bleak and it scared the hell out of me. But I always wondered what life would be like in a limited nuclear exchange. I had played Dungeons and Dragons as a kid and the game had it's own hellish lands, but I never came across anyone playing something world ending like Dark Sun, though I did play Gamma World once.
Now that I am a fossil, it was weird seeing 5E D&D gain mainstream attention and it peaked my interest. Eventually I ended up in an OOTA group of 20/30 somethings from 2nd level all the way to 16th for almost 5 years. Throughout this campaign we dealt with faerzress and wild magic brought me back to wanting to create a campaign world that is not damaged, but still functioning and still under threat of destruction from the same enemy. As much as I wasn't a fan of Independence Day: Resurgence, I think of Grage similar to that movie with a slightly less lethal but much more powerful enemy and a still divided world post uniting against a common enemy.

The Overused Raven Queen:
I have no issue with the Raven Queen, but the 5th level retcon of her has DM's shoving her down the throat of way too many Hexblades.