A random thought that came to mind.

BLU essentially has access to every element since spells come from enemies.

Maybe for BLU revive the elemental wheel from FFXI with updates to existing spells or the addition of new ones that would allow possibly a perpetual combo wheel of sorts rotating spells based on element they are classified under?

Granted mostly elemental resistances and mechanics were pretty much phased out to simplify the game as a whole but they could still have a niche for specific jobs like BLU to add depth to the gameplay.