depending on how you look at the game you can say it was more about aries then cloud.
I very much agree with you. I mean, her face is shown in the very first scene & the very last (not including 200 years later).
I don't think her impact on planet was any less than Cloud's was.
also think of it this way. cloud killed sephiroth but even if he killed or didnt kill him meteor was still on the move. but then mako and aries white materia came and saved the day. even in the end she was a main factor to saveing the world.
lynx
beaten final fantasy III,IV,VI,VII,VIII,IX,X,X-2,XII,mystic quest, tacitcs, tactics advanced, crystal chronicles.
you only live once but if you do it right once is enough