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@doctorbadwolf, I have ongoing campaigns for both Eberron and the Forgotten Realms, but I also do have my own homebrew world called Tor-eal. It's a far-future version of the Forgotten Realms where the Blood War ended, the Devils conquered all of the Outer Planes (and Astral), and most of the gods are dead (only a dozen or so remain).
My world only has the Inner Planes (and Ethereal Plane, and an added Dream Realm, and the Far Realm still is out there), but all of the planes are highly developed and important to the setting. The Shadowfell in my world is home to a holy war between the followers of the Raven Queen (Shadar-Kai, Risen Kenku, Shadowfell Firbolgs name "Sharbolgs") and the followers of Vecna (Two undead-touched races, one for incorporeal undead and another for corporeal undead, Vecna's hordes of undead, the Dhampir). The Feywild is home to the Archfey and the Courts of Seelie and Unseelie, as well as quite a few player options (Fairies, Satyrs, Dryads, Centaurs, Fey-Goblinoids known as Boggartkin). The Plane of Dreams was created by an invasive Elder Evil from the Far Realm that transformed the Demiplane of Nightmares into a way for it to study and experiment mentally upon mortals while they're sleeping using its aberrant servants (Dream Watchers, giant floating eyeballs that shoot eyerays of psychic energy, and Dream Snatchers, giant floating hands with a thumb on each side that grab dreaming souls for their experiments).
The Elemental Planes are where many magical resources come from, like Adamantine from the Elemental Plane of Earth (which is mined by a race of Dwarves that gradually merged with Earth Genasi), water and food from the Elemental Plane of Water (which is inhabited by Merfolk and Locathah), and magical, always hot furnaces for blacksmiths from the Elemental Plane of Fire (which is home to Firenewts, Volcann Goliaths, and and Azers). The Celestials that survived the conquering of the Outer Planes by the Devil Legions emigrated to the Elemental Plane of Air and founded a society of angels, archons, and couatls there (including many Aasimar, Air Genasi, Aarakocra, and Couatl-Yuan-Ti inhabitants).
The Material Plane is a diverse land, basically the "melting pot" of races, with many of them having very unique cultures. Goblinoids have a Magocratic-Theocracy where they worship magic and have crusades against aberrations and psionic peoples, Minotaurs have conquered all of the major forests and banished the Elves to the Arctic (they also have an extremely militaristic and dictatorial society, and are obsessed with both mazes and gold for some reason), Orcs generally worship Ubtao (who is now the God of the Wilds) and are the protectors of nature (having a rivalry with the Minotaurs), and so on. There's also a few new races, like the Golmeng (golem-people with 5 different subraces for different types of golems; Chelmic for alchemically-made clay-golem-people, Immurts for adamantine/iron-golem-people, Gragnef for stone-golem people, Jemlin for gem-golem-people, and Prysmex for glass-golem-people), Felshen (psionic people descended from a now-extinct race of flesh-golem-people that were a 6th subrace of Golmeng, and now have a religious rivalry with the magic-worshipping Goblinoids), and the Ecubi (Incubus/Succubus descended people with wings and shape-changing abilities).
The world is also split into a bunch of different nations, like Lantanea (far-future Lantan that has developed extremely advanced technology that they've combined with magic and is home to many artificers and where the Golmeng and Felshen were originally created), Wadhaven (a democratic-nation that stretches from Waterdeep and is bordered by the High Forest and Neverwinter), Nevumber (a dystopian nation centered on Neverwinter ruled by a triumvirate of dictator-mage-kings, where teleportation magic in or out of the country is impossible, with giant, 200-foot-tall metal walls surrounding the whole nation), Sylvarin (think a future version of the Silver Marches with a half-elven monarchy and a parliament). There's also a Draconic Empire (northeast of the Silver Marches), kingdom of Giants (south of Waterdeep, north of Baldur's Gate), and a diverse swath of nations/towns for the main races/species in the game.
It's a huge kitchen sink, and I have way too much lore about it, but I like huge kitchen sinks and lore, and so do my players.