Frionel:
Weapon - Two Swords, then end game: usually Masamune (gotta love a haste sword ) and a Blood sword (if you don't know the power of blood, don't ask )
Magic - sort of red mage-ish (Cure, Fire, Bolt, Ice, Esuna, Exit, and Life)

Maria:
Weapon - Bow early game, Powerful Canes if I find them, then back to Bow when i get the last one (Yoichi I think)
Magic - Strong white, light black magic early game, then use elemental weapons and items if needed later. (Aero/Bio 16 cane pwns Thunder Gigas )

Gus:
Weapon - Two Axes, end game: I forget the axe name
Magic - bout the same as Frionel

Leon:
Weapon - Swords, end game: the other Blood, and I forget what the other powerful sword was.
Magic - Basic white magic (Cure, Life, and Esuna if I really feel like taking the time.)

If i'm trying to speed thru the game, every character gets Swap, including the guys who come and go. Holy, Flare, Ultima, etc. I really don't care about, they're pretty useless at the time you get them anyway IMHO