So. I was playing through the game again recently and realised, Tifa, Red XIII and Cait Sith have to be the only characters with their heads screwed on correctly.
Tifa, a completely normal girl, just watches crap around her unravel and reacts in a completely sane way.
Red XIII, however oddly wise, still thinks about the best course of action in every situation.
Cait Sith (Reeve), Although being a cat on top of an obese moogle, Is still a Shinra Executive who makes a decision to join AVALANCHE in saving the world after the destruction of Sector 7, while still looking after the people of midgar at all times.
Now Cloud (laughs), just thinks he's Zack, then Cloud, then is just generally confused. He doesn't give a shit about the people in the world, as he keeps saying through out, and concentrates on getting back at sephiroth and jenova.
Barret is a glorified Mr T. gone wrong. He's decided to become a terrorist after Shin-Ra raid his hometown and killed his friends. He straps what can be said to be a miniature cannon to his arm, swears a lot and is generally irrational about most things apart from separating into parties, which he is surprisingly organised about. He generally develops a concerned outlook for the planet through the game, however keeping his irrational behaviour.
Cid is haunted about his failed dreams and so smokes his days away in the tomb of his unlaunched rocket next to his house, while verbally abusing Shera for making him cancel the launch. He develops some sort of
sympathy and determination to save the planet after finally getting into space, focussed on saving the planet, and if that means going into the deepest plunges of the earth to fight monsters that will probably cause him to have many more dreams of anguish and malboros, why not. Definitely the Closest to Barret.
Vincent is constantly a haze of mystery, he's a genetically altered human being, with no sense of an ego, and his personality resembles that of an uncaring member, only thinking about Lucrecia and Hojo; an obsession gone wrong. He puts himself to bed for 5 years, is scared of his true power, and only joins the party for the chance of confronting Hojo, in which he only says that Hojo should be the only sleeping. His cold dialogue even makes Cloud's "I don't give a shit apart from chasing down Sephiroth" mindset quite warm in comparison.
Yuffie being the youngest member is a lot more upbeat, probably from week-long partying on acid at her mansion in Wutai (Which is quintessentially, Japan, in terms of landmass/shape). She has no real ambition to face off Sephiroth, or save the planet, and is just in the adventure to get the Materia, and get out, which she suceeded with if she didn't get captured by Don Corneo. Obsessed with Materia, she continues throwing up on every moving vehicle throughout the Journey, just for the hope of bringing materia back home.
The AVALANCHE motto, keeping the team together through silence, stare-down and poison;
"theres no getting offa this train we're on"
who's going to get on with you lot on board?
Sanity of the Characters. (spoilers) 
