Minimalistic D&D Setting

D&D is a neat system with too many things to keep in mind. Spells, legacies (also known as races), capabilities of people, monsters and their abilities... and that's just the rules. On top of all this, there's stuff like geography, history, and so much more. If you think all of this is easy to manage, bear in mind that you're probably still thinking only about the Material Plane, and not about all the other planes of existence. While I'd love to be a DM someday, I know that I would much rather work on Runehack than on whatever world I run my D&D campaign in. Running a game of D&D in Runehack would require me to drop the vast majority of classes, my own system for games in Runehack is being worked on (with heavy quotation marks, since I keep getting distracted), … Wouldn't it be nice to have a low maintenance world to run D&D games in?

I felt creatively drained when I started to write this, but it's a subject I've been thinking about for a long time. It only makes sense for me to post it here, hopefully I get some sort of response to see what I could improve on it.

The land of million possibilities. Except it's lands actually.
Storm Wars, by Elena Konstantinova

Minimalistic D&D Setting

During the war of gods, all of the planes of existence have crashed into one another, leaving only two: Material Plane, now made up of planar remnants shaped like flying islands, and the Ethereal Plane, which was untouched since it overlaps all of the planes according to its lore. Personal name for this world is "Vestigial Itonia", but that's just for the ease of personal use.

Each island is a closed system, unless it has a way of traveling to other flying islands. Islands flying in parallel trajectories are rare, but not unheard of. Each island is a microcosm of its own, taking on characteristics of a plane of your choice, or a combination of planes. All of this in mind, chances are this island hadn't been visited by anyone, or it was, or it was visited and colonized too. In order to navigate to a specific island, you need a compass made out of special rocks inside of the island the compass points to. Cardinal directions are determined solely by celestial things, like the Sun and stars.

People need to traverse the islands somehow, so there could be three broad ways of achieving that (plus combinations), consider which of these is the most commonly used one. Not all islands are guaranteed to have access to any of these. Listed in an order in which I would expect them to appear in the world history-wise, these are:

1. domesticated flying creatures,
2. magic,
3. technology.

I like for all the islands to have the same gravitational orientation (same "down"), and for the "bottom of the world" to be filled with a dark Void that the Sun goes beneath to create a day-night cycle. Since rich get richer, I'd assume there would be 1-3 big countries that are spread over many islands and try to colonize more at all times, so that could be a simple way to bring player characters together.

What do we achieve with a world like this? The lowest maintenance world I could think up.

• It's not necessary to figure out a big picture geography of the world, which makes it easier for the DM to draw maps of individual islands. No need to make the land fit a bigger environment.
• Each island can have its own history, and if it's a closed system, its history could reasonably be unaffected (and unaffecting) the world outside of the island.
• When the DM and players feel like it, they can visit all sorts of planes of existence, including nonexistent ones. Want a candy island? An island populated only by the bears? How about a mixture of Elemental plane of fire, Carceri, and Feywild? Whatever that would be like, you can just decide to have an island like that fly by, and give your players an offer to fly there. If they don't want to, you can also just... have the island never appear in the game again.
• This kind of world can support pretty much any player option that the player could want to pick. On one hand, plenty of uncommon species could be unfamiliar to the wider world, which could make general population suspicious of players who choose unusual races. On the other hand, with such a huge variety of races, they might also all be accepted equally. Both can work well, whether applied to the whole world or to the individual exceptions.
• Tying it to the previous two bullet points, does your player want to make up a corner of the world to call their own? Be it their birthplace, the island they wanted to visit all their life, or the isle where their mortal enemy sits upon their iron throne? All of this is very much doable!

… wait, is this all just One Piece but without water and with D&D's magic replacing all of the magics that are in the original story? Wait no, this world doesn't have a famous pirate announcing a race for the biggest treasure of the world that's located on an island which hasn't been finished by anyone but him and his crew for centuries. So of course this isn't One Piece!

Thank you for reading, and have a great day!