It seems that FFXIV is your first mmo then, all fine friend

I'm going to explain it a bit deeper then

. There is an incredible amount of possibilities to make the gears armory working into an horizontal progression design like :
- adding partial and full set bonus on "named-gears" with skills/stats/jobs stats/etc,
- being able to improve your best equipements with specific enhancements (in this case it could be materia but why not something else too !),
- re-using your previous piece of gear into a specific craft as a base material to make it stronger or more specific (stats wise) into something you are aiming for,
- storyline achievement gears that are just "too good" to replace, like a ring or an earring (is Rajas Ring ring like a bell for everyone? xD),
- legendary weapons questline, no, I'm not talking about our current relic weapons

, they actually missed the opportunity by making them a "catch-up weapon" before getting the last "top tier endgame weapon", it's lame, very bad design to me x.x, last coil shouldn't drop them
directly, it could be mandatory to "beat the hardest boss" to improve them but nothing related to the system we have now.
- mixing endgame crafting material drops with non-tradable items in order to craft powerful equipements,
- funny armory with weird, bizzare, odd, untypical stats like enhancing your chocobo exp gain rate or your "skills" while watering your personal garden plants xD
To be honest, this is just a couple of exemples of what we could get, there is no limits to a game designer / developer creativity.
That's why the current gear treadmill is looking a bit pathetic to say the least :x, new major update : player n°9255478 will replace his full armory ilevel 110 for ilevel 130, the differences? more base stats number and that's it, see you in 3-4 months to do it again.