As big of a fan of Yasumi Matsuno's work, Ogre Battle, Vagrant Story, and FF Tactics, FF12 is something he should have been ashamed of. This is akin to how disappointing San Mendes's 007 SPECTRE film was. Such a capable artist in his field, well proven after such great hits, given a huge budget, and producing some of the worst crap in the franchise history.
If you ever played Xenoblade, a similar, but far more advanced game, FF12 will feel unrefined, unengaging, and disappointing. Ultimately, FF12 was clearly rushed and unfinished on the content side. There were huge areas that should have had more to them, people, objects to interact with, anything. It is likely they got cut due to time constraint, so it was bad budgeting on scope as far as Square's part.
As far as original, it was hardly such. The game was pretty much lifting mechanics from online RPGs and not doing a lot to make them feel engaging compared to other RPGs at the time. Rewarding the player with more flexibility in the mandatory auto-battle system as they leveled up was dumb. Very sloppy design.
The story was derivative, and the characters were dull. Vaan was pretty much a remake of the monkey-kid from FF9, except somehow even shallower of a main character; easily the most shallow FF main since the NES. The closest thing to good character in the game was Blather, a very poor attempt ripoff of Skies of Arcadia's Gilder.
The Final Fantasy series is great, but FF12 is simply not up to par; even FF13 was substantially better. It somehow managed to feel both bloated and lacking in substance at the same time. In my opinion, the worst FF game since FF2 on NES.