i am honestly so friggin picky, it's a wonder i ever chose anyone, lol. my villager choices depend on a lot of things - species, personality, vibe, actual character colors and attributes, og clothing, og interior, exterior, some concrete element of realness or plausibility, popularity, uniqueness as compared to my other villagers, etc. and yes, haha, these traits all do have to adhere to a set theme for my island. so for NH i have been looking for bright colored, poppy and unique characters with some take on modern tech meets plantcore/green design theme, to match my overall island theme. it's highly specific so it's been a bit of a challenge, which i love tbh!!
a good example of this is: drift! a rather unpopular (why tho!!!) jock frog that is much cuter than most other jocks, bc he's super small and designed after a poison dartfrog, with creative patterns and a happy face. his house has great wooded elements on the exterior, and the interior is take on a rokker theme without being overwhelming. it has a tool shelf, ironwood furniture, succulents, a fern, throwback skull and a dj table. he also talks less about constant exercise than other jocks i've seen? for sure its one of his hobbies, but i also see him just wandering around, exploring stuff. all these elements together made him a primo pick!
i do all my villager research upfront and dither for a long while before i go out and trade for them and even then sometimes i decide to let them go, if i'm just not vibing or i have too many villagers that feel too similar, lol.