The chocobo is just a mount, you ride it to get you from point A to point B faster, I think having it on 20 mins cooldown is too much, perhaps not having cooldown would help making people explore the game and use teleport less, so they can appreciate the game.

And add mini-games for chocobo's, racing, digging etc, and add some mini quests that gives you rewards, like armor or gear for your chocobo (with some speed increase perhaps? 10%-20%-30% speed increase if you equip certain gear on their feet or whatever?).