pros:
Everyone would have to hunt their own items to level their own crafting jobs to meld their own materia for their own relic quest.
No would would buy carries and there would be no RMT
Houses could be made through crafting instead of payed for.
Some things would take longer to accomplish keeping people subbed longer, and giving them a sense of achievement that simply doesn't exist when you just buy it, everyone wins.
It would do none of these. Players would pick an item to become the de-facto currency. If you've played Diablo II: Stone of Jordan. If you've played Asheron's Call, Pyreal Motes or Cracked Shards. My guess is that in XIV, it would be the elemental shards that crafters use.
-People would be paying crafters in shards.
-RMT would be selling shards (as if they aren't already)
-People would be buying carries in shards
And the other two are pretty self-explanatory.