Oh yeah, story is number one priority in an RPG. I can look past shoddy gameplay if it has a great story, the first Suikoden didn't have that real gripping storyline. Although I had just gone through Chrono Trigger and Final Fantasy VI for the first time, so anything was going to pale in comparison.
I thoroughly enjoyed FFX up until getting stuck (I'll beat it, someday), but it was mostly a how a great RPG should look and play rather than a great story. Story is good and all, but nothing new really with no real HOLY SHIT moments. But the battle system, graphics, challenge, and everything else is damn near perfect. I don't have any interest in FFX-2, the whole pop singer thing looks pretty vomit inducing.
I don't really know anything about XII, but XI I never played and didn't really want to. I've never played a MMORPG and don't have much desire to, I prefer immersing linear console games to PC free-form any day of the week. Although Morrowind is mighty fun.
Oh, and it looks like Ys VI is being released next week for PS2, I've been waiting TEN YEARS for another Ys game, part III was the last released in the US.