You can't get Ribbon? Suuuuuuuuucks.
I for one placed Ribbon onto my armours as soon as I could. Leaving 3 vacant slots. These slots would be filled depending on the character; I dislike giving everyone the same abilities.
I discarded magic completely once I was dealing around 60,000+ damage with normal physical attacks, so I had Wakka, Yuna, and Tidus - none of which had the greatest of defensive values, so I gave them all Auto-Protect. Yuna is essential for healing, so I have her Auto-Haste. The other two had Auto-Regen in its place (though that didn't really become too useful until I had 30,000+ HP for each). Yuna's final ability for armour was Break HP Limit, naturally.
The remaining slot for Wakka and Tidus wou--- well now that I think about it, most of my slots were the same. xD These two would be given Auto-Phoenix. I'd have the same set-up for all on different armour except for Regen and Haste - they would be replaced by Auto-Potion for the battle with Penance.
As for stats, I maxed out Speed. Wakka and Tidus would have max Strength and Accuracy, along with very high Magic/regular defense. Yuna would have all this excluding Strength. I replaced that with Magic. Hp would be ever increasing, and MP around 999 (seeing as Yuna only uses MP at this point - I didn't get Break MP Limit, and even then only uses 1 MP per spell.

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