FFXII was far and away the best PS2 entry. I consider it the best FF since FFT (yes, better than FFIX, I know that's heresy at EoFF).

I can sympathize a little with people who didn't feel attached to it partway through the first time. I felt the same way myself at first, as the way the story developed was poorly done. The dungeon crawling aspects overwhelmed the cutscenes for a good chunk of the game, and the pacing was dubious at best. But all told, the story was pretty great. I think XII is one of those rare games that actually improves substantially on subsequent playthroughs when it's easier to appreciate all that's going on.