My god, that was a terrible summary.
Your just looking at the plot stripped down and it's general overview, of course everyone is going to use the generic good guys vs. bad guys plot. And of course the good guys are going to win, what? Do you want to play a 50 hour game and have the main character killed and it doesn't give you any type of aftermath whatsoever? Making you feel like you wasted 50 hours of your life. Be realistic, and enjoy the contents of the game.
FFXIII and its friends will attract costumers, seriously.
I doubt three games are worth at maximum 400$...
There was a rumor a while back that if they did make a KH3 it'd also be on a different console, unless Sony can really really pick up pace, I'm guessing the Saturn will be repeating it self sometime soon.
Weither or not you doubt the games are woth 400$, people will buy it anyway. That's like people buying the PSP for popular series like MGS or Silent Hill. Hell, not trying to badmouth the Wii, but it doesn't have a whole lot of good games either, it maybe be only about 200, but people are buying it for Super Smash Brothers or Mario Galaxy, that's all I hear about it. Nobody brings up Metriod Prime 3 or anything. The Xbox360, while it has a lot games, it has a 70% fail rate, but people buy it anyway, even after they've been through 2 broken ones already. People have gone through 10, but they still buy a new one, and yes, some people just buy a new one rather than send it in for repairs.