It's all about the AV to me, sorting out based on usefulness from there. I'll use cool looking less effective moves to finish off bosses, fight randoms, etc. and sometimes... just because I feel like it.
Tank Drop (WA4): Just fought Belial, and while she only got to use it twice... it was a tank being dropped on the party. Yes.
Hand of Fate (SoA): It's Drachma flying through the air with a robotic hand that's twice his size and landing it on the enemy for massive damage and instant death.
Tatsumaki Zankantou (SRW:OGs): Real men ride other men. Also, incredibly high powered attack running off of Zengar/Zanger/Sanger's melee stat.
Genocide Circus (WA5): My favorite Combination Art animation, and one of three that I made use of aside from looking cool, due to using Carol and Rebecca a lot.
Akashic Buster (SRW:OGG) OGG version specifically, for the flourish at the end. Favorite animation for one of my favorite originals, and spammable as heck once you get the morale.
Lionheart (FF8): Omnislash, only way cooler.
Shining Binds (ToS2): All the hi-ougis got a big visual upgrade, but Shining Binds was already the best of them.
Fever Time (TotA): Fireworks!
Silver Nightmare (SoA): Puppet show!
And some really cool usefulness.
Intrude (WA4): Already have good memories of Raquel starting off turns with 75+ FP.
Grand Cross (FFany): If you aren't loaded up on Ribbons, this is THE attack you least want to see at any given time. Nearly had to retry Necron in FF9, except Berserk Freya and Zidane, the only ones left alive, took him down. Add Night Queen (P3) to this, for similar reasons.
Aura of Denial (SoA:L): The reason to use Gilder. At least, I think it blocks ID, and necessary for a few bosses here and there, like Daikokuya.
Baton Pass (PKMN): Ever fought a well played BP chain? Mostly applies to the metagame.
And this.
Metronome (PKMN): Clefable used Metronome! Clefable used Explosion!
Proooobably remember some more later.