Now, that probably wouldn't quite work as such for XIV. The closest analog I can imagine, with our netcode so badly restraining PvP, would be the likes of significant synergies (or, generic skills that previously differed merely in their appearance actually taking on undermechanics befitting those skins).
For instance, imagine if Shadow skills, as used by DRK and NIN, made use of actual shadows, and were thus affected by other skills that generate light. With that, you've suddenly got these rather specific comps by which to milk that aspect for all its worth: <Black and White> as a WHM, DRK, BLM, NIN or SCH, DRK/PLD, RDM, NIN comp by which to take advantage of (Ver)Flare into a brief AoE Bunshin, or use DRK's Shadowskin or SCH's Fey Light as a way to longer maintain Shadewalker on the tank or on particular enemies.
Of course, that's probably wonderfully fun, but the base concept were done in very particular ways as to allow for a sort of self-balancing, it'd create heavy upkeep costs and may constraint future encounter designs (even if, on average, it'd be allowing for more depth per fight).
For a moment, let's go back to the idea of "complexity that leverages visuals."
Let's start simply, with just two jobs of the same role. We've got Monk, and we've got DRG. Having no prior knowledge of them, a viewer might quickly notice that:
- The "Monk" attacks quickly, typically with blunt weapons.
- The "Dragoon" uses a longer-than-average weapon, mostly stabbing, and can... jump high??
Personally, my goal, and the basis for later "utility" would be to ensure that those basic differences
matter.
For instance, maybe we could differentiate weapon types via a "Stagger" system, whereby the "blunt"-er the weapon (or strike), the more immediately and briefly it imparts that "stagger" (variably suppressing progress towards further actions). Thereby, comparatively,
blunt attacks could better control mobs in the short term, while
slashing and, increasingly,
piercing attacks could better wind down or bleed out enemies. Or maybe there's a destructible armor system, to some similar effect.
Next, let's consider range. Maybe the longer your weapon, the slower, but also the longer your range. Thus a Dragoon could keep to some extent an enemy at bay out of that enemy's reach, while a Monk would instead have to rely on its attack speed to beat the enemy to the punch, so to speak. Whatever.
There are plenty of ways to cover this, and plenty of ways to go from there, but that's where I'd usually prefer to start.
Just my food for though / $0.02.