My end game party was this
Tiz - Pirate/Time Mage
Edea - Spellfencer/Red Mage
Ringabel - Swordmaster / Performer
Anges - Spiritmaster / White Mage
Anges would be main healer, Edea as backup. Default every turn with Anges and heal when necessary. Tiz and Edea would mostly just attack until things died and Ringabel offered attack up spells via the performer abilities when they were needed. Suited me just fine. Good tip is to find a strong weapon, give it to a character and then find out what class has the S rank proficiency with that weapon.