I hate comparing this game to FF XI because it isn't trying to be FF XI but -

[Ryans]

FFXI was just a more expansive game from the ground up. It has varying job combinations and varying stats that can allow for a lot more customization than FFXIV. With all that potential for customization, FFXI could pump out new items with different special stats that could be used in conjunction with older gear to give the biggest combined boost to, say, haste or you could have a different set of gear if you were focusing on Store TP.

FFXIV could go the same direction, but I don't think it will because it is focused more on casual players. Yoshida has said he wants an expansion every one to two years with a level cap raise with each one. That doesn't leave much time to design multiple sets of gear (plus the content to go with it) for each job all of equal strength, but a focus in different areas. It also doesn't leave much time for players to get the select pieces of gear they want out of multiple sets even if there was more customization choices, which I assume will come with time.

Even though I prefer horizontal progression, a linear vertical progression is easier to manage and design and it's easier for the average gamer to participate in.