I like exp grid for several reasons including: 1) you can make Yuna a blk mage to make the most of her high magic stat 2) you can get a thief earlier and more easily 3) you can get yr characters higher agility and/or haste, so speeding up the game.

Two thieves and two black mages are excellent for use in and around the thunder plains. Steal off cactuars and blast iron giants with double watera. Yes you could use Kimahri in the original grid, but he is slow and weak magically compared to Yuna.