Ashe: Red Battlemage because Best Job for Best Character. I got her Shikari because Ninja Swords but other than that, I have no interest in the second LB.
Penelo: Machinist. I never used ranged weapons in vanilla, was curious to try them out.
Fran: Foebreaker, because I needed a tank who hit really hard.

In the wings...
Balthier: White Mage.
Vaan: Monk
Basch: Time Battlemage.

I have no desire to second job things up as it seems to defeat the whole point of the one job "challenge." This game isn't very hard as it is, if I start stacking all those HPs and Battle Lores, we'll be unstoppable.