The next time you want to extend one game's length, try innovating or creating content. But please, avoid forcing the players to grind levels from the very start of the game }:(
I don't know if it is a big, lengthy game or not, but it is the hardest Final Fantasy I've touched. Apart from the initial cave, I'm having to grind levels to be able to do anything "not from the main quest". And even there it is dangerous; if you have bad luck (a lot of so hated random combats), yo can die.
Usually, level grinding is performed optionally for one of this reasons:
- Lowering the difficulty level: If enemies are level 5 and you level 15, you will have no problem on killing them.
- Balancing speed-runs: If you're going too fast across the main storyline, probably you'll end facing an enemy or boss that you won't be able to kill until you level up.
- Grinding money or items: Along with experience, monsters usually drop money and/or items, so it's like a 2x1, extra levels plus extra gold.
- God feeling: If a level 5 enemy is easy at level 15, imagine being level 50 or 60, it's almost like being a god. *
I at last don't see in that list something like "Make the game last longer", because that's a cheap and dirty trick.
* Beware of games that auto-level enemies acordingly (like Final Fantasy VIII)