personality analysis of sorts
For some odd reason people often think Rikku is childish, hyperactive, a scaredy-cat, and dumb. Others view her a a girl who has endured harships and is very determined to help those in need. It seems the only thing anyone can agree on when it comes to Rikku, is that she looks good in a bikini. So, let me break it down to you with examples:
Is Rikku childish? Yes, to an extent. She is only 15 at the start of Final Fantasy X, after all. She is often described as the person who keeps the group in high spirits, and is the only one to help Tidus in their all but doomed quest for an alternate way to defeat Sin. Considering that Yuna did not die, I would not call it naive, or being childish in one's dreams and hopes.
How about in the sequel? At times it seems that Rikku was more mature in the original game, even though she was two years younger. But at the beginning of X-2 there are no worries. The Gullwings are merely enjoying their life, gathering spheres. Rikku is still the upbeat one of the group, who raises everyone's morale -except Brother's. When talking about the Tidus-lookalike and Vegnagun, though, Rikku seems to sober up. She is not brightest rat in the box (because this is a Yuna-centric -game and all), but that does not mean she does not care. Because finding Tidus is so important to Yuna, Rikku does not joke around about it. And, believe it or not, 17-year-olds even in real life are pretty childish.
Okay then. Is Rikku hyperactive? Does she have ADHD? I doubt it, even though she does move around a lot...Like I said before, Rikku is a girl who likes to see smiles on everybody's faces. She is constantly cheering others on and trying to lighten up the mood, but I don't think it's nearing hyperactivity yet. She can be serious about things, too.
Moving on. A scaredy-cat? Hardly. In FFX she is afraid of thunder, possibly of the farplane and dead people coming to eat her brains, and that Yunie would die. But may I remind everyone that she overcame her fear of thunder by camping out in the Thunder Plains for a week? It is natural to be afraid for the safety of those who are dear to you, and I doubt anyone would remain cool when attacked by dead people who can transform into monsters. I know I wouldn't. Rikku's fears show that she is not inhuman, and that she is someone people can relate to. I would be extremely bored if any of the main characters wasn't afraid of ANYTHING. Because c'mon, that doesn't happen.
Oh, what's that about hardships that I heard? Well, Rikku is Al Bhed. Al Bhed have always been a target of prejudice and many Spirans loathe them. They did not have a home for the longest time. And when they finally get one, it's destroyed by the Guado. Rikku's mother and aunt died when she was little, other Al Bhed friends are turning up dead here and there, her cousin is walking to her doom....it is probably because of this that Rikku tries to keep a light mood on the party.
Rikku jumps head first into new and interesting things. She loves to help out, take Yuna, Clasko's chocobos, and Tobli for example. Anything to make the world a better place and to have more people happy. And this little analysis has turned into a sort-of in defense-rant. I'm sorry.