^That is wrong on so many points. Lightning is an OK ravager, shes an above average commando, she is one of the worst medics available.
Lets see...
Fang:
Best commando
Sharing best place Saboteur with Vanille
Second best sentinel (she got less health than Snow, that's about it)
Sazh:
God as commando post game (70K damage PER GUNSHOT with blitz! Do you understand how fast that is? Still, Fang can still hit harder if you exclude the blitz and that she got genji gloves)
Pretty good ravager (the lag time helps ALOT)
Offensive synergist (got all status buffs except Veil)
Hope:
BEST Ravager due to having the highest strength
Defensive synergist (got all status buffs except Vigilance)
Sharing place as best medic with Vanille
Lightning is far from the best in the game. You'll see later in the game.
I also used Fang, Lightning and Hope through the story. Post game I switched Hope for Sazh and his godlike gunshooting abilities.
Also, Cold blood is just as good as Army of One and Highwind is godlike.
In the end, Lightning is good. But got less health than Fang and Snow, less strength than Fang, less magic then Vanille and Hope. She ain't the party leader for me, I'd rather use Fang or Sazh which I usually do use.