I focus for now on mining class more than any other. I like the leves. Here is what I would like to change:

1) anima cost reduced so when I gather leves in all towns and teleport to complete them, it doesn`t cost as much OR chocobos at all camps. I don`t want to walk to save animas, please? My time is precious.
2) eliminate the need to check a website to know the hotspot. Give me a manual of mining I can acquire each 10ish levels through guild-points and then ease my life - I have no memory at all. This is good for any class in fact, I hate going to websites it breaks the game immersion. Make it an in-game wiki, why not?
3) I agree with Veasna, we need a better system than the current text to pinpoint where to go (as an option if desired). I would personally prefer an onscreen compass combined with flashing dots on the map with different colors depending if it is on the same level, lower or upper level (or level 1, 2, 3).
4) To make gathering more interesting, you can either improve the mini-game, or improve the environment (immersion). Currently, I would prefer the improvement of the latter. How about specific zones (dreamlands) for gatherers? Thinking of the game Flower on PS3 here for mood/environment, just as a rough idea. Crafters could even contribute in building these environments in synergy with gatherers with exclusive rewards.