The thing with Final Fantasy is, its fine to reinvent some things, but the game has to be an RPG at its core.
FF12 was an RPG, but not enough JRPG. The problem with the game really was the story. While it was brilliant at some parts, for the beginning of the game it was very difficult to feel the characters were important. I remember Basch was meant to be the main character, and he should've been.
The game was very good in terms of RPG elements; exploration, customisation, weapons, armour. monster hunting. This aspect was nearly perfect.
The problem with the game was really the lack of a character driven story until the half way point.
By the way the story was very intelligently written, because the events taking place within the game are a reference to the events of Hiroshima and Nagasaki. In the same way Matsuno designed Final Fantasy Tactics after the War of the Roses, and Tactics Ogre over ethnic cleansing in Bosnia during the 20th century. Shame he didn't get to complete the story his way, instead of Square Enix interfering to appeal to their kiddy demographic.