MY ultimate FF VII party is either Cloud, Cid and Yuffie for the simple fact that if you go into a fight with all three of their limit meters charged (and they're all high level with their best limit breaks equipped), then you can unleash around 300,000 points of damage in 1 round without expending a single MP. Nothing beats an Omnislash-Highwind-Doom of the Living chain, with the exception of W-Summon-Knights of the Round-Mime ad infinitum, for taking down tough bosses.