It was an alright game, but there were some fatal flaws that kept it from being great.
Firstly, the graphics. One of the best parts of the game is the graphics. The scenery is amazing and each area is done excellently. The only badly done image is the main character's abs. (Honestly, it looks like he used sun lotion to draw the lines for abdominals on his stomach, and then shined a tanning light on his torso for ten hours.) Other than that, it was great!
Secondly, I'll discuss the plotline. While it wasn't necessarily bad, it was quite a bit more confusing than those of past games. The political plot of Final Fantasy XII was a little hard to follow at times. A knowledge of political progress and flow is pretty essential to fully understanding this plot. Furthermore, towards the end of the game, many overall points are left completely unexplained and leave the player wondering "who, why and how?". Also, if you're a fan of the summons of the past games, say hello to them in airship form. This game introduces new summons. (In a rather bland way, if I do say so myself.)
Also, the main cast of this game is generally unexciting. Not to say that the party is useless and boring, but in comparison to other games, the characters did not stand out as much. Plus, while most Final Fantasy characters are known to have completed many amazing feats of mystical proportions, the FF12 cast participates in the story in a more or less down-to-earth manner, making them not quite as outstanding.
Next, the battle system of this game is MUCH different from past games. Rather than breaking off into a separate scene to do battle from standing in a line, the characters will take on all enemies and bosses on the ordinary map whilst running around the field. The ATB system is still active, making the freedom of movement less useful, but the position of characters can affect the outcome of both an enemy's area attack and your own support actions. Overall, it can make or break your team.
The leveling system is still the same as most past games. You gain EXP from enemies and level up at certain points, but the ability and equipment system is a huge change. Like in Final Fantasy X, there is a grid system, but it is different yet. There is a large board accessed from the menu which turns out to look a lot like a game of Scrabble. Using License Points (LP) gained from enemies, (similar to past "AP") you can purchase licenses for your characters which allows them to use/equip any magic or equipment that you've purchased. Here's where the License Grid becomes like Scrabble. You can only purchase licenses that are touching already owned licenses for each character, with the most expensive, valuable, and useful licenses being around the edges and backed into corners. Familiar, no?
Overall, the grid isn't a bad addition, but it can be quite maddening, especially if you don't have the route for your licenses planned out. (Although, why one would need a license to do such things as wearing hats is beyond me.)
Lastly, the exploration. The concept for the traveling is excellent. In most past games, the player had the freedom of traveling the world map, which was welcome, though very unrealistic. It indeed did offer a lot of freedom though. In Final Fantasy X, they decided to make rid of the world map for a more realistic look, and instead lined the areas up to give the impression of real life travel. However, players complained that this change made the game much too linear, and that it took away the liberty of traveling.
So, in this game, the world map is absent once again, but instead of the areas in the world being lined up to simply prompt you from one spot to the next, there are many different paths you could choose to branch out. For instance, the game's main city has three exits to the east, west, and south, all leading to different destinations (which, in turn, will often branch to new places themselves), and the player will often return to the city to begin the next journey to a new destination.
This was a great way of remedying the visual problem of the exploration of the game. The player still has freedom, but now the cities aren't for some reason miles away from each other separated from by mass, barren expanses of flat land. (Plus, the player will no longer dwarf the cities.)
This game with a tragic downside, however. There is a lot of space between each destination now, with the game often requiring you to travel through several different wilderness areas to reach them. This causes the game to become quite tedious, (causing me to only pick up the controller every other month for a few days, but that's just me). Now, this, in itself would not be so bad if it weren't for the level of enemies every time. Basically, if you simply leave your leveling to the main storyline, battling only the enemies you need to encounter, you'll end up being underleveled. I'll say this: This game can actually be TORTURE for the underleveled character.
This does have a remedy though. If the you choose to accept, you can take on many sidequests, most notably, hunts. Much like in Final Fantasy Tactics Advanced, you can visit pubs to accept jobs which you complete by defeating a certain enemy. These hunt "marks" act as minibosses, and will vary in level as you progress through the game. There are also many sidequests you can partake in to defeat optional superbosses and to acquire optional Espers (the summons, which are mostly modeled after enemies from the Tactics series.)
Overall, this game was BAD, per se, but it could have done with a LOT more flash. Some parts really made me want to sleep, while others just left me confused. As far as Final Fantasy games have gone, it wasn't the worst in the main series, in my opinion, but I think that with Square's advancements, it could have been a lot better.