I absolutely hated XII. Once you had the right gambit setup you could literally walk through the game just pausing for the occasional battle. It made things so boring.
Conversely, if you did not do almost every single side mission, then you could not level up enough to get through early parts of the story.
Plus, the graphics were awful! Everything was rendered in little blocks that rarely lined up together properly, and it was painful to look at. Granted, it was on the PS2, so it is somewhat surprising that it worked at all. Should have been a PS3 title.
But, if they fix the rendering engine, re-balance the early game play, and make gambits more interesting and involving, then I might give it another shot when it eventually comes out on PC. At least they had a somewhat interesting story and world to explore... just need to fix the 'game' part of the game.