I've seen a lot of posts talking about wanting NMs from FXI, which I didn't experience but I understand what they are, and other open world elements. I think that the fundamental complaint (which I sympathize with, even if I don't have a burning desire to see it implemented) is that there is not the possibility of something unusual happening to you while just traveling around the open wold of Eorzea.
This is something that I think the original Everquest did a great job of, and I think it would be something easy to implement over a period of time or in a future expansion that would satiate the open-world desires of most sand-box players to a small extent.
My proposal would be to add in "Named" monsters into the spawn-cycle of each major area in non-city zones. The general idea would be to slot in a "rare spawn" for any spawn spot of a certain monster type. For instance, any Amalj'aa monster in the Zan'rak camp would have a .25% chance to spawn as a "Named" mob. The named mob would be marginally stronger than its cohorts, perhaps with a special attack that would make him more difficult to defeat. The mob should be soloable by a character slightly over-geared for the zone/regular mobs, but tuned towards at least 2 characters going against it.
The best part - the loot of course! And none of this treasure map stuff with crafting items and 1500 gil. I would envision it to have 2 drops, a rare and a common drop. The rare should be i70 for the level 50 mobs, and the common would be i55 for that level. However, the best part about these items would be that for a, say, level 30 named mob, the item would be level 30 to equip, but it would be i37 for the rare, and i33 for the common - making them the most powerful level-appropriate items pre-endgame.
That would allow for alt-gearing and a nice boost to the economy as well, as people often buy gear for their new little alt jobs as they level up! I know that I would be in the market to spend 10-25k on a chest piece and weapon 7 iLVLs above my lvl 30 BRD! Especially if it looks cool for vanity later on.
The amount of item slots available would NOT eclipse the usefulness of crafting for these levels, it would just provide people who wanted to go out exploring an alternative way to make gil, and provide a fun surprising element to a tedious quest or hunting log!
For example, in the Zan'rak Camp:
Mob: The Zan'rak Orator
Level: 56
Abilities: Paralyze, AoE Knockback
Rare Drop - Zan'rak Ritual Staff
Two Handed Staff
Can Use: WHM/BLM/CNJ/THM
iLevel: 70
Level required: 50
Vit: 16 | Int: 26 | Mnd: 26 | Flm Res: 25 | Accur: 27 | Det: 27
Common Drop - Zan'rak Ritual Beads
Neck/Wrist
Can Use: PUG/LNC/ARC/MNK/DRG/BRD
iLevel: 55
Level Required: 50
Str: 4 | Dex: 4 | Flm Res: 9 | Crit: 20
The items would be a little outside of the norm, you see the staff has low vit for higher int/mnd and some bonus Flm Res since its an Ifrit item, and the beads have low str/dex modifiers for the item level, but a bonus Flm Res and a huge bonus to Crit, making the items unique and a lot more flavorful to gear your characters with.
With 2.2 the new items would have to be beefed up in level, by the by!
Just a fun idea I thought I would share - I wouldn't expect this to be able to be added into patch 2.3 or anything, but maybe if we can get enough support for this, or a similar idea, we could solve the problem of the homogenous gearing options AND the (relatively) boring open world!