yeah, i think it'd be good to have elves be really like... convinced of their superiority over all other races, because i think that gives more depth to half-elf characters, and then i think there should be like... villages surrounding major cities that are lived in almost entirely by one race, but other races pass thru (think Chinatown or Little Italy), and then maybe areas of the continents that certain races are more likely to come from (this doesn't have to be decided/set-in-stone but it could be part of a character's bio that they came from, say, up in the mountains where a lot of Dwarves live, so they're not used to seeing other races.)

then besides that it'd be cool if everywhere else was a pretty even mix of all the races, and have the most uncommon thing be for someone from the undead continent to be in the living continent and vice-versa. like, there's definitely a good number of undead on the living continent, but they get weird looks everywhere they go.

also, one of my characters is a Tiefling, and i'd been thinking of him as being alive, but since he's demonspawn and demons are more undead than they are alive imho, i wonder if he'd be sort of trapped in between. oh! or, like, the living human parent of a Tiefling who gets stuck with them when the demon leaves always dumps their kid in the land of the Undead. The undead, in general, would be much more tolerant of Tieflings but still really suspicious of them.