By scope, I mean that the game is entirely limited by transportation. As your transportation improves, the size of the world increases. At one point, literally when you leave a floating island in favor of an entire world.
And - here's the start of the issues. At the end of the game, you get the ability to temporarily fly higher to go over small mountain chains. You never get the ability to fly over mountain masses, and this leaves the world always slightly cut off. In the plot, you never have to really go a huge distance, but the game is not designed for you to go from plot point to plot point. The second you start going back to grind away or to check side quests, the inability to go certain ways becomes more and more annoying.
Add in the fact that the second best ship is actually almost too fast for comfortable flying, and the best ship is as slow or slower than the walking speed. Why downgrade speed? Is it due to processing power and the size of the ship? Why not make the ship smaller and allow faster travel? You never need to race in the best ship. You cannot give up the mountain climbing in favor of the fast ship, since every late game dungeon needs the mountain hopping. And due to the slower speed, it'd take longer to swap ships.
Then - there's the job system. You're not told how it works. There's a reason.
Up to about level 60 in a job, it takes 6 moves (any move) to gain a level. After that, it's about 8 moves to level. Any move. Including guarding. You can store - I believe, 12 moves in every battle toward your levelling. You can't level until you finish a battle. One level per end of battle. So, let's do the math, 12 moves per battle, 2 levels per battle, 99 levels per job. That's 40ish battles. The last 30 levels need 30 more points, so about 3 more battles. The most efficent way to do this is to go to the lowest level area, guard for 12 turns, kill the monsters on your twelfth turn. The better you battle, the faster you win, and the less job levels you get. The job levelling system is entirely metagame.
So, why does it matter? You're competent enough for almost all the battles in the game if you're level 20 in your job. You only need about level 60ish for the final dungeon. But - let's say you're a thief. You use steal, you get a potion. You steal from a boss. You get a potion. Why? You need to be at level 70 to get anything usefull from a boss. There's, as best I know, about only two bosses in the middle of the game that have anything worth stealing. You're never told this.
You can't get the best jobs in the game until you go to the final dungeon and beat the first boss of the area. These have the best stat gains. Levelling up the earlier jobs is almost pointless when you get the final jobs. The jobs have another problem. You see, the jobs are sometimes required for plot reasons. For example, the plot may need you to be a mage. You must spend time 'adjusting' to the new job with lowered stats. If you don't know what's coming, you'll find yourself forced to wait out your adjustment time and then wait out your new adjustment time to be ready for an area. Also, your warriors will be stuck being a mage temporarily.
The DS game had added characters and they spread out when you gained various characters. For the most part, there's no relevance to their backstory once you get them in your party. The ending does not resolve any of their issues. The online stuff offers special weapons and quests, but without it, you've got no way to open these quests. They need a fair amount of dedication from another person with the game, since it involves a few steps. This seems like a stupid way to hamper the game.
Ah, well - at least some of the characters are cute, and when you get it working, you can make amazing teams with Bards and Dark Knights that make you feel incredibly powerful.