Chocobos in FFXIV if I was game designer:
1) Chocobos can store inventory items.
2) Certain places cannot allow chocobos, so you have to pick your items b4 you go in. This will limit job changing in certain areas and create a bigger challenge.
3) Chocobos can be ridden anywhere they are allowed.
4) Chocobos need to be caught in the wild Avatar style by defeating it, then riding it.
5) Chocobos can eat some of the drops you get from mobs and get bigger, and store more items.
6) Chocobos can be called with a chocobo whistle.
7) Chocobos can race each other on a track with many obstacles. You can throw stuff at other people in the race to slow them down, also avoid stuff on the road like banana peels, mario kart style. All sorts of prizes can be awarded.