She was my favorite character in the game and it affected me powerfully when she was killed. It certainly had the desired effect of making me want to kill Sephiroth. I enjoyed using her both as a PC and in the storyline.

My initial reaction was of course wanting her to return, even by some implausible means. But upon further consideration, her martyrdom is what makes the story so powerful.

Events in AC have only reinforced this, as I didn't find it touching that her ghost is benevolently haunting Cloud, I found it creepy. I think it would be for the best if she simply rejoins the Lifestream completely and becomes reborn as something else, unless she's trapped as some sort of guardian of the Planet now.

That being said, I'm glad at least there are alternate worlds (like in FFT), where there are parallel versions of her wandering around.