If it is put in, then a Jump similar to FFXIII that is only reactive to certain elements in the scenery/environment in my opinion is the way to go. Part of the main reason that I play FFXIV (and played FFXI) is for the battle tactics and team work, not to jump around as if I'm playing Super Mario. I can see why some people will argue for it and I understand their point, but for me personally (and this is just my opinion) I don't want to see a Jump button added to the game.