We'll have to agree to disagree there. I loved the 12th addition to the series. FFX was brilliant, granted. I preferred FFXII because of the improved combat system, stronger story, some homogeneity to "A New Hope" etc. On top of this I liked the fact that different weapons were good for different occasions, e.g. the ninja swords were brilliant against Yiazmat (Hardest) but would have got you nowhere with Zodiark (2nd hardest- best esper). In my opinion anyway.
As far as the story goes, I would say it's stronger than in FFX. This is because it constantly shifts unpredictably, the events about Bur-Omisace threw the end further away than I would have expected up to that point. In FFX it was quite predictable what was going to happen after zanarkand, you knew that Tidus and Yuna would fall for each other, the only surpising bit was right at the end. Turned out Auron was wrong, Spira wasn't Tidus' world after all.