I heard about that scene, X-Maniac. It would've been good to see.
I agree with Angamb: it shouldn't have been deleted in the first place.
But that scene, even if it had been included, doesn't make an arc. And that was my point: why give Storm an origin scene if you're not going to develop the character more?
In X3, Storm's character seems mostly buildup, but no payoff.
She is against the cure, but when the one person who's basically the reason of its existance walks into the mansion, she doesn't even have a comment on this.
Same in the final battle, when Wolverine suggests they should cure Magneto, shouldn't she have some objection against it? Sure, Magneto is a great threat, but her views, as established in X1 and 2, are pretty much the same as Magneto's: why should mutants be "cured"?
I'm not saying she should go into a long debate with Wolverine and Beast, but a comment like "I'm not sure this is the right way" or even a look that suggests she isn't happy with this decision could have done it.
Also, Xavier names her his heir, but when the time comes to take that position, she chickens out. And that while at Xavier's funeral, she pleaded that they, his students, would have to carry out his vision.
I think that if they had followed through on all the things they set up for Storm in X3, we would have gotten a very interesting Storm, that still could have been a logical continuation of X1 and 2 Storm.