I've actually found most of the armor I find in chests and put up on the AH sells, and it sells for a decent penny considering it isn't very good. I mean it isn't enough to fund my BST's pet food bill or anything but people are willing to pay several thousand gil for items that are really not very good. So I think it wouldn't be unreasonable to add, say 9 sets (mage, light, heavy X3), one at level 30, one at level 50, and one at level 70. After that it gets easier to gear, and before that most people (including me) use the chocobo shirt/hat and w/e else since everything is SO SQUISHY.
