Vaan : shikari+bushi
Balthier : shikari + foebreaker
Fran : white mage + machinist
Basch : knight + bushi
Ashe : black mage + monk
Penelo : white mage + time mage
Vaan and Balthier being best candidates as the two Genji glove + ninja sword users, Vaan getting dark blade and Balthier having every break.
Basch being a knight in the story knight + bushi was perfect for the tank/decoy.
Machinist goes to the person with weakest stats and works well with white mage so Fran got both.
That leaves Ashe and Penelo with the highest magic stats. White mage and time mage for ultimate buffer amd 2nd healer and for nuker it was either black mage monk for holy and general purpose balanced nuking and high level white magic to stand in with heals without swapping or BLM/RDM for Ardor. Pick whichever.
Gave hastega to Fran instead of Renew to Ashe as Ashe as BLM can heal over 10k to the whole party with just curaja anyway.
The best weapons in the game aren't job specific so it really doesn't matter.
Just completed the Platinum last weekend.
Im always obsessed with perfect builds and it really doesn't matter here. Worst case you can auto script it with fail proof gambits and throw ribbons and white masks on everyone and cheese Yiazmat with reverse and decoy with the starting weapon and AFK the Platinum overnight if you wanted.