It could be that the Samurai is a melee DPS.

The Red Mage could be a DPS/Healer with a mechanic that works like the fire/ice mechanic for BLM. Cast healing spells and you get a buff that makes your healing spells better and your dps spells worse.

The Dancer could be a dual weld evade tank with high dodge and evade.

Just a thought I had.