I LOVE this game. 25 hours in and I can say pretty confidently that this is my favorite FF game so far. And I've played 7, 8, 9, 13, a little bit of 15 and 10 (maybe a couple hours, but not enough to count them out), 7 remake, and the GBA ports of of 1 and 2. Never tried 6. So there are still some contenders I have yet to play.
This game just hits all the right notes so far. The graphics are incredible for a PS2 game. When people say that games at the end of a console's lifecycle are always the best looking because the devs know how to get every ounce of horsepower from the hardware, this game should be part of that convo. It seriously almost looks like a PS3 game.
The fighting is so perfect, and I love the way the gambits play into it, though it's definitely not without some (infrequent) frustrations.
The pacing is great, with new areas being introduced frequently. The variety of areas and environments is great, they all look fantastic, are generally pretty open, and offer a lot of exploration and non-linear routes to your destination. The cities are detailed, inhabited by lots of NPCs, and look alive.
Some of the dungeons are stunning and well designed. Puzzles are easy as is pretty typical for FF. Enemies and especially bosses tend to be pretty challenging the first time going through one of these areas. Some bosses initially seem unbeatable, but there are often clues as to how to beat them in these cases.
The enemies in general are nicely varied, rendered right out in the open (as is the fighting), and they manage to look incredible despite this.
The story is... there, though this is the least interesting part to me. The characters are well done and the voice acting is good, though the audio quality is a bit dated sounding like there's something missing. It reminds me of the voices of mid-20th century Disney movies (Cinderella, Robin Hood, Jungle Book, etc...).
I'm really blown away by how good this game is. And equally baffled that 13 was the follow-up to this, because that game missed so many marks.