Mang why you gotta tempt me like dis
The PC-98 crew would exist, so that I don't have to come up with stuff for them. Except Yuuka.
Reimu would be an airheaded American kid, chewing bubblegum and chattering her opponents to death.
Marisa would be a very generous Korean girl that insists on wearing traditional garb, and always apologizes immediately if she thinks someone else is offended by her actions.
Rumia would have eyes that radiate brighter than the sun: She has to wear sunglasses strong enough to blind her to avoid blinding everyone else.
Cirno would be a meek fire fairy, afraid to use her own powers: Daiyosei bullies her into causing trouble every once in a while.
The Scarlet Devil Mansion would actually be a group of small, competing gangs that generally don't get along: Meiling's group specializes in infiltration and never gets enough sleep, Patchouli's thugs put Cho Aniki to shame (and Patch herself is secretly illiterate) with Koakuma as the real brains of the outfit, Sakuya leads an Italian-Mafia style outfit of butlers that take great pride in their padded shoulders and would be dangerous if they had enough sense of time to be coordinated in any fashion, and Remilia's group consists of a bunch of dark-skinned snipers that loathe physical contact, with herself having a severe phobia of blood.
The Crystal Rainbow Troublemakers are kept in check by Lady Flandre, an eternally-calm creation goddess that cleans up their messes between constant outings from her plantation to sunbathe.
Letty would be a hotheaded (no pun intended) summer youkai, oddly reminiscent of Mario 3's Angry Sun.
Alice would be a toddler version of her PC-98 self, being raised by an adult-sized living doll named Hourai.
The Prismrivers would be a trio of deaf artists that prefer to communicate through elaborate drawings/paintings/etchings made within seconds.
Yuyuko would be a lich necromancer, with Youmu as her most successful and long-lasting reanimation attempt (despite a little bit of exposed skeleton). The PCB 'incident' was over Yuyuko refusing to eat until her phylactery was found (even though she hid it herself to get away from Youmu's horrible cooking).
The Yakumos would be reversed in power level, obviously: Chen as a beautiful and ancient nekomata that tries to make herself look ugly just to piss off Ran (and everyone else), Ran as Yukari's emotionally-abusive, distant 'mother' constantly ashamed of her tails and trying to hide them, and Yukari as a shy little girl that tries too hard to please everyone.
Suika would be a cherub, constantly trying to play matchmaker. She's allergic to alcohol.
Wriggle would be a neat freak with a severe bug phobia.
Mystia would be an optometrist. A very near-sighted optometrist.
Eintei would be themed after Native Americans, with the rabbits and 'lunarians' in an uneasy truce. Eirin is the only one with a nearly-ineffectual gun, which she generally fires to scare off the rabbits beating Kaguya senseless as she charges into battle for no good reason. Reisen is a brawler best known for punching people hard enough that they throw up their lunch, and Tewi is a very young, very honest rabbit that manages to keep the two groups from REALLY trying to kill each other.
The rabbits and lunarians are searching for their missing, warring deities; the sun bull Keine and water swan Mokou. The two are rumored to fight every sunset somewhere in the barren deserts.
Lord Aya would be the slow-footed, secretive ruler of the Tengu, constantly trying to censor contact with the rest of the world. Tenma smuggles out everything anyway.
Medicine would be a nigh-invisible ghost with a purification field of sorts around her. She's very social, but since most people can't hear her, she put up with a lot of abuse from the few that could until the 'PoFV' incident made her presence public knowledge when she exposed the Pearly Gates.
Komachi would be a rather sadistic angel at heaven's gates, regularly bemoaning the lack of suicide candidates to arrive. But she loves her work all the same, what with all the death tales to hear. Shikieiki, on the other hand, constantly slacks off on janitorial work in favor of cheering up souls uncertain about their qualifications for Heaven. Often this entails getting drunk out of her mind.
Rin Satsuki also made an appearance in the incident as an ever-present, talkative stalker that made sure no one would ever forget her. Ever.
I think that's enough for now.
