Anyway, to the OP.
Space Fantasy!
All DnD races are present, as well as anything from Star Wars that anyone wants to port over and give a brief translation into the setting, or just any ideas that anyone has that flow from the particulars of the setting. For instance, a player was reading about some species of moth that lives on gas, I guess? And the same day, I was talking about how there is Aether gas that can be breathed like oxygen, but isn't as comfortable for most species, and allows for things like Aether sailing vessels in space, but can also be gathered to use as a fuel, to power all sorts of magitech, and sometimes condenses into crystals. So, we got nerdy and built a race of moth people who live in the Aether clouds that form in solar systems and anywhere where people and magic gather.
The most common races in the Galactic Commonwealth of Free Planets and it's closest neighbors are, Gnomes, Elves, Firbolgs, Goliaths, Genasi, Humans, in that order, and then everyone else in little enclaves and such spread throughout Commonwealth space.
The Arkosian Kingdom is primarily Dragonborn, Lizardfolk, Dragons, Kobolds, and then small populations of most everyone else.
The Illithid Collective is mostly Gith, Genasi, Tieflings, Duergar, and Illithid, but other populations are growing as the Collective expands it's reach, and it's diplomats infiltrate the other powers. This is complicated by the Rakkma Alliance, which the Collective brands as treasonous terrorists, but who in turn claim that the Great Elders of the Collective are terrible monsters, and that the Illithid are performing horrible experiments on unwilling subjects, and using mind control to expand their power.
The Unified Human and Demihuman Authority, known elsewhere simply as The Authority, is a Corporate-Fascist expansionist state that considers itself the true heir to the first human galactic empire, which lost a century long war with the old Federation of Free Planets 1000 years ago, before the Star Lanes vanished and all the old empires were broken or folded in on themselves. It is a pretty terrible place to live if you aren't a human, and not great if you aren't a particular kind of human. The Authority planets were fringe colonies of the Human Empire who split with their cousins when the Humans signed their peace accords and joined the Federation. The colonies accused their leaders of treason and cowardice, saying that the New Frontier was the birthright of Humanity. Bottled up by themselves for a thousand years, this poisoned well festered, and when the Star Lanes opened up again, the began spreading their disease at the end of energy cannons. This is also the only place where the term Demihuman is considered an acceptable thing to call anyone, ever, for any reason.
Mostly human, about 15% other folk, mostly "near humans" like elves, dwarves, halflings, and genasi. The only non humans who are treated as human are aasimar, who are valued under a mythology that they are humans with a divine blessing, and that only those of pure lineage are born with The Blessing. Aasimar who don't look the part tend to be shunned and quietly ignored. This is here to give the setting a place that needs to get burned down.
The Baronies of Nea Thera are the old Core Worlds of the old Human Empire, including it's capitol city-planet, Nea Thera. Now, they are the front line of the war to keep the Authority from taking over the galaxy, and their folk are often known as Borderlanders. The Barony Paladins are elite troops who patrol the Baronies in heavily armored mech suits, while the Border Rangers are expert pilots, scouts, and skirmishers, often seen riding arcane mechanical mounts which can take control of simple or willing arcane systems, like the Rangers' ships. An offshoot of the Border Rangers exist in the Commonwealth, who also have these mounts. The Baronies are primarily Human, Halfling, Warforged, and Shifters, with strong minority populations of Kalashtar, various beast folk, Aasimar, Tieflings, Goblinoids, and then small minorities of everyone else.
Running around through and between all these regions are the nomadic people of the Galaxy.
Vaes Shadar - Natural navigators who are able to sense celestial alignments, and use this gift to be ever seeking their lost home. Shadar-kai, Vryloka, with small numbers of "adopted" folk of other lineages, mostly hexbloods, dhampyr, and various mixed race folk and supernatural human lineages.
Kobolds - Often ride on the body of cosmic dragons, in a symbiotic cycle. Do not try to commit acts of banditry against such kobolds. Their dragons sleep, even while traveling the Star Lanes, but they can be woken, and they are hungry when woken. And they love their kobolds.
Vistani - A traveling culture of many races, some say related to the Vaes Shadar, some say not. Humans and Halflings are most common, but gnomes and tabaxi are also common sights on Vistani ships.
River Folk - Mostly halflings, it is generally agreed upon that this is how halflings have always lived, even before they left whatever world they first emerged from, so long ago there is no record of it. Hin ships are swift, light, manueverable, and surprisingly comfortable, even for bigger folk. Often seen manuevering around bigger vessels along the Star Lanes, trading wares, working as tinkers and mechanics, running "food truck" style restaurants, and simply enjoying the company of all the sundry people that can be found on the big interstellar superhighways.
I'll make another post about Islands World, later!