I can help! My NPC list looks like this:
Spoiler
Show
[Spring Prince] Cornelius Talmage
Male Spring Court Fairest Muse
Madly upbeat used car salesman
“Seize the day, no matter the cost”
Hans Gruber
Male Autumn Court Manikin Elemental
Hobo King
“Why make something if I’m not getting paid for it?”
Robert Cludge
Male Winter Court Gristlegrinder Ogre
Cannibal construction Worker
“I’m sure the smart folk will work it out.”
Ecetera. Gives me a simple, flavourful platform that I can leverage into more detailed personalities if the PCs take a shine to them. If the PCs ignore, kill or overlook them, then I haven't wasted a lot of work/don't need to shoehorn them into the story.
Peripheral NPCs can stay in the periphery, never becoming more than their outwards appearance would suggest (unless you decide to step them into the spotlight). Important NPCs become increasingly elaborate, with aspects of their personality discussed, revealed and explored on. This technique works
decently for tabletop games (you sometimes have to think really fast if the PCs unexpectedly, say, go for a jaunt into the NPC's Astral Space) and
excellently for PBPs (because you always have time to think between replies).
More examples in the NPC cabals section of
Skyscraper Graveyard.