WARNING!
The following post contains talk about World of Warcraft! FF fans with weak hearts should avoid the following post!
Right, with that warning out of the way, I figured I'd share a memory of mine from back when I played World of Warcraft. I had already leveled a few characters up to 80 (this was during Wrath of the Lich King), and as a result already had access to the major "Gear-Crafting" professions. Figuring my next character would focus on one of the crafting professions dedicated to something other than gear, I went ahead and had my character pick up Engineering.
For those not in the know, Engineering was a very odd profession. Almost nothing it offered was usable by non-engineers, and mainly consisted in the early stages of various types of explosives, a few common-quality guns, and some scopes for improving said guns. However, the further you got into the profession, the more interesting things started showing up. Things such as an accessory that would either shrink the target or shrink you; A helmet that could be used once every 10 minutes or so to hypnotize the target; mechanical baby dragons that would fight alongside you for a few minutes. There were also a few pieces of actual crafted gear (Again, Engineer only), that were actually on par with early-endgame gear, and as they were all somewhat steampunkish-looking goggles, had a unique appearance that no other piece of gear offered.
Once my Engineer hit the level cap, though, the REALLY fun stuff came into play. You see, by the time of WotLK, I guess Blizzard realized that any profession that wasn't Enchanting, Jewelcrafting (or whatever it was called) and Alchemy was essentially worthless, due to most raid-level gear being vastly superior to crafted gear. However, rather than make crafted gear that was equal or superior to the stuff you could find in the cutting-edge raids, they gave pretty much every profession self-only 'enchantments'. In FFXIV terms, this was like giving every DoH class special materia only they could meld, they could only put one such materia on each piece of equipment, but said materia could be applied to ANY piece of gear that occupied the proper slot, even the equivalent of Allaghan gear. On a related note, they also made it so that the gathering professions had their own bonuses, like bonus Crit Rate from Skinning and a self-heal from Herbalism.
Now, I'm not saying SE should do something exactly like that in FFXIV. Something like that would be horribly unbalanced with the current approach to crafting classes. Rather instead, what I think they should do is make it so that, while you can still unlock and level every single crafting and gathering class in the game, they should make it so you can only 'dedicate' yourself to a couple of them, and your dedication allows you access to these types of bonuses.
Say for example you dedicate yourself to Goldsmithing. Once you hit a high enough level, you gain the ability to turn, let's say, two random Materia into a piece of Materia with "+5% Healing Potency" on it. You can then meld this materia onto your Garuda EX healing ring. However, you still can't meld regular materia onto this ring, and if you want to meld another Goldsmithing exclusive Materia, like say "Freecure Frequency Up", you have to destroy the old exclusive materia first.
Anyway, tl;dr WoW actually had an interesting idea for how to make crafting professions relevant in the endgame, and I really hope that once SE can devote time to non-critical stuff, like making Crafting useful even for the very late endgame tier content, I hope they try something similar.