Tifa is stunning, but it was after Cloud's mental breakdown and invalidity in the Lifestream that I became particularly drawn to her. Tifa was the one who entered the shattered fragments of his mind and gently encouraged and coaxed him back into control. Sephiroth's plan would have succeeded if Tifa hadn't intervened, and Meteor would have destroyed the planet.
Tifa is a true unsung hero, with the heart and face of a loving angel.