I also used my Aeons as meatshields...unless I wanted to be a prick and totally obliterate whatever fiend I was fighting at the time.
Sometimes, if I'm feeling lazy, I'll toss a Petrify Grenade. If they are immune to that I just spam quick hit or just use regular attacks.
As for magic, I use it every now and then against the Flans if I'm not strong enough to overkill them with a regular attack.
And I use the overdrives when/if I feel like it, or if I just want to be a prick.
As for Nemesis, I spam quick hit until It's about to get a turn, then summon an Aeon to take the hit. Once the Aeon falls, I just spam quick hit again, and use overdrives once the gauges fill. And repeat as needed until Nemesis falls.
As for Sin...it doesn't matter what I use, I overkill him in one hit. Same with Braska's Final Aeon, and Yu Yevon.
Half the time I don't even finish the game anymore. I normally just play the game through, max out everyone, get everything and play Blitzball or I just frequent the arena...at least there I don't kill stuff in one hit, and I still have a SMALL chance of getting my ass handed to me. (Auto-Phoenix is nifty
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