i would switch the White Mage to a devout...because Arise(full-life w/e you wanna call it) is lvl 8 only and the White Mage can only use up to lvl 7 magic...and see in the final boss battle and even some boss battles after the earth crystal good luck going on without Arise...but dont use the sage because he has the weak versions of the summonings, and he also has a lot less MND INT and MP

but personally i used Summoner and Devout...Summoner because of the High MP and INT and the AoE attacks...and the devout for the REALLY high MND and MP...

but its all up to you =)