This is just a few tips I've come up with when doing worldbuilding pages for Kanka to help keep things concise and avoid monolithic races that end up all acting in one specific way. These are not laws nor gospel, just suggestions as I do a lot of this writing myself and while I'm no professional I do think a lot of these help me to keep from writing something in a way that not only stifles someone else's character but also helps to flesh out the world and keep things interesting.
Tip 1: Using groups instead of one race.
One of the easiest pitfalls I found was grouping up an entire race together. Since we did the Dawn of Worlds game to make the world it was fairly easy to categorize an entire race the exact same way, but this tends to lend to a very stagnant and samey vibe for the characters of that race NPC or PC or otherwise. Personally, I suggest breaking them up into groups, and then get into the nitty gritty of how they might act, their history, relationships, etc etc. It's fine to make a racial page for Humans, but it's even better to make a Family page for a group of them like the First City noble houses or the Road Knights. A good example of this is Soleil Lo Rainard, Lune Lo Rainard. and Lo Rainard done by Caleb. Three different pages, one for the base race and two for it's subraces, gives you plenty of room to flesh out each individual feature of the subraces and how they might interact with other races, their history, social castes, etc, while retaining the base race's overall information without typecasting them all. If it isn't a subrace and just a different faction, break them up using Families instead of Race.
Tip 2: Maliciously steal from the Forgotten Realms Wiki
I fundamentally refuse to apologize for this one. Someone already wrote out all the info you're going to need if you're writing up something for a non-homebrew race or even just a location, you may as well just take the pertinent information from the wiki and slap it in, adapt whatever needs to be adapted for Falanar specific races or subcultures, and you're off to the races. It is 100% easier to rewrite something right in front of you than it is to write something out entirely from scratch and it gives you a chance to learn the lore of the race if you haven't already. This information is there for you to use, use it and adapt it how you need to, nobody is going to judge you for it. An easy example for this is the The Everstar Isles was essentially just me picking and choosing interesting bits of lore from other areas in the Forgotten Realms like the Moonshae Isles, Chult, etc.
Tip 3: Tropes can be good
While avoiding harmful stereotypes, you can use common tropes to help flesh out the meatier parts of an entry and save you a bit of time wracking your brain trying to remember every little detail about something. Typically finding 2-4 tropes helps me settle on an idea, and I may not use them all in the end, but it gives me something to work off of. Greedy dwarves with gunpowder weapons and being good blacksmiths were three of the four I settled on, easy enough to find on TvTropes and I knew a few offhandedly from other media in general. Pick a few that play well together, write something up for them, and you've got most of the defining characteristics of a good subrace or an area.
Tip 4: Just fuckinnnnnn steal from other media
Every DM does it, why shouldn't you? Like the way that group of mercenaries is portrayed from your favourite Fantasy show? Make them an entry in the world, maybe add a few splashes of your own personal flair or a trope you really like, and you're done. Not every single creation we make needs to be a wholly original idea dragged from the folds of our brains, sometimes it's easier (and more fun) to just grab something you like and adapt it to the world we're playing in. D&D, Forgotten Realms specifically, is incredibly forgiving for stuff like that from the ACTUAL REAL LIFE HUMANS of Mulhorand which were just egyptian people teleported to Faerun all the way to Ed Greenwood literally writing himself into his book series and making Earth a real place. The reason I pushed for us to still be in the Forgotten Realms world was so it was much easier to diversify Falanar by pulling from that continent, but if you wanna make the Night's Watch from Game of Thrones there's literally nothing stopping you besides...maybe changing up the name a bit. Immersion is still a little important.
Tip 5: Not everything has to be described logically
I've been watching the Harry Potter movies and I appreciate that a lot of the magic is not hard magic, it's not defined entirely and it's not all explained in depth every time it shows up, and it's a good tip for writing as well. Does your city float above the clouds? Excellent, say it does this via magic and call it a day. Basically what this means is that you don't need to elaborate on every little detail of your world, sometimes you can simply let it just be the way it is and move on, don't let yourself get bogged down in the tiny details unless you're willing and wanting to spend an extra two or three hours writing out what you're writing.
I'll add more tips as I can think of them but these are the ones I try to keep in mind mostly. If you have any suggestions please let me know.