One thing:

The random treasure system -
When you're getting a high-end piece of armor or weapon, there is nothing more irritating than spending an hour or so going back and forth to the chest over and over again seeing if it spawns or not, and even if it does, seeing if you get that right item or not.

btw, I think Vaan looks good. I even thought at one about getting a hair-cut similar to his (even dyed to the same/similar color). lol

I like Larsa, too (currently have a desktop wallpaper of him).
One of the things I like about him is that he gives out free hi-potions as another person suggested. This way, you can save your mana by not having to use healing magic or your own hi-potions. I hated that he left your party when you arrived at that temple.