The SKs have stopped caring about killing all the non-humans a while ago. Otherwise the Cleansing Wars would’ve restarted after Borys calmed down. So you could easily have a bunch of weird critters in a city state. It’s just the cities are still primarily human with most other races distrusted and/or treated as second class citizens.
Here’s an example of some various characters, though these were all intended as rival “adventurers” you can always tone down the concepts. I took some extra time to give each character a “hook” of sorts.
Halfling Beastmaster: A master of the wild with countless animals at her command, she wanders the wastes seeking the home she was separated from so long ago.
Half Giant Honor Guard: Once a soldier of Destiny’s Kingdom, he had been assigned to a Templar travelling to Balic. However most of the caravan was wiped out by dwarven banshees. Now he has wandered to these lands alone with a sealed scroll from Hamanu and no idea where Balic is.
Thri-Kreen Huntress: A slayer of beasts and men alike, she savors the hunt as much as the kill. One day she shall return to her clutch with a prey worthy enough that she might claim what was always her’s.
Dwarven Champion: Blessed by both his ancestors and the earthen spirits he is somehow able to wear armor carved entirely of stone. Currently he is on a quest for the earth priests of this land.
Half Elf Bard: Raised by mummers she has learned the best way to get ahead in life is to know what others didn’t and to be well liked. Yet the promise of riches has gotten her in trouble more times than she’ll admit, forcing her to wander the lands in search of fortune. What she doesn’t know is that one Dune Trader house has a long memory indeed and has been hunting her all the way from Nibenay.
Elven Defiler: Great secrets lie buried in the ruins of Athas. The sorcerer kings would see that only they and their’s hold the keys to sorcery. Yet he knows better, through delving into the bones of dead cities he has mastered sorcery and now seeks his greatest prize yet. The spellbook of a dead kaisharga.
Mul Enforcer: She would’ve been condemned to the life of a laborer or pit fighter had her wild talents not emerged. Instead the patriarch of House Ankhar of Tyr found use for her as a bodyguard and enforcer. She knows this is the best life she can hope for, she was taught as much from childhood. That is why she serves them now in pursuing their lost heirloom, the Jade Crow, than flee to find a life of her own.
Edit: Here’s some unconventional races as well
Ssuran Gladiator: It is one thing to make a mammal bleed and die, it is another to make the death sporting. His scales are stronger than most armor and his strength outclasses a mul, but it is the handicaps he gives his prey that make the crowds love him. For this one? Just his claws should be enough. That one deserves to die to a sword. For her? He will strangle her to death for his adoring crowd. It is good to be champion. Yet some whisper the mul gladiator Demgar holds a greater following still in the black arenas of Tyr underground. He will find this mul and eat his heart before the guild thieves of the hidden city.
Tari Alchemist: This ratlike creature is a forager without peer, she concocts poisons, brews, and tinctures of remarkable potency. Yet the reagent she desires most is the sap from a tree of life.
Gith Oracle: Paired with his own wild talents, the spirits of wind have blessed this gith shaman with superlative foresight. Yet his warnings to his tribe went unanswered. Instead they welcomed the silver swordsmen into their caves. The visions were clear though, the children of Vlaakith shall doom his people to slavery. Only at the buried city of Zerthimon will he find salvation for the lost children of Gith.
Villichi Monk: A wandering psionic warrior, she is fascinated by the lands beyond her convent. Yet news has come to her of several nearby villages who have had their psions disappear in the dead of night, including two villichi children. Only one body was found, partially buried in the sand. Her brain had been eaten…
Aarakocra Bounty Hunter: None can wander as far through the wastes as he. The mammals are easy to follow, it is bringing them back alive that proved hard at first. Bolas work well, as do truncheons, poison darts, and terror. Today though he hunts an altogether different prey, a runaway Templar.
Dray Firelord: His people had been abandoned by their own god, cast aside as imperfect. Unlike many of the cowards within his tribe content to beg their absent god for its approval, he knew there was none to be had. Instead he wandered the wastes for months, seeking a new purpose. He would find it north in a land of black stone and flaming water. The spirits of fire spoke to him and told him of how sorcerers cursed this world to suffering. Yet if he could sacrifice seven defilers to the hungry flames, they would mend his broken body and make him whole.
Grimlock Barbarian: To live one’s whole life underground is to be free of the hateful sun. Yet food and water are if anything more rare. His people would hunt the surface dwellers in the dead of night, feeding their brains to the great worm and consuming the rest for themselves. It was during one such raid that a sandstorm separated him from the others. Lost and alone it was the mercy of a human caravan that offered salvation. His strength kept them safe and spared him a life in chains. Recently an expedition has formed to explore dwarven ruins from the green age. He knows those tunnels. He can’t let them disturb the worm god. If they do, everyone will die.