That'd be quite an improvement, but I honestly just wish they'd entirely remove Materia-as-items. There are a number of ways to go about that, though, from the minimalistic to more ambitious.
The Minimalistic:
Slightly More Ambitious:Let it take after job-specific Bonus (Secondary) Attributes. As one does content --be they quests, instances, leves, or anything else that previously granted Materia-- they generate AP*. Each tier, the AP cap increases (e.g. 600 in the Abyssos tier, maybe 640 by next). This customization is done through job-specific plates, whereby one sets up to 5 stat goals in order, such that the last is the dump stat (e.g., 6.33% Haste if possible -> 12.5% Haste if possible -> 20% Crit if possible -> Equal Crit and DHit dump).
I.e., a customization system done in the most convenient way possible... that also happens to slightly shrink the brief, minor inertial advantage of raid gear. No Extract Materia chores.
Gil sink and crafter privilege to be made up elsewhere (e.g., by offering enhancements to the armor itself, attachable without item trades).
* (AP = Aetherial Power, per old FF Ability Points, since Materia Points would look like Magic/Mana Points; Dynamis [Points] is likewise spoiler-y and has a not-great acronym.)
Perhaps Yet More Ambitious:The same as above, but the stats are applied through actual Materia. Each job can select up to 5 materia and spend any amount on each. But, since it's actual materia now, we should go a little further. For instance, we might create a few classes of these.
Common would be your plain secondary stats: Haste, Determination, Critical Hit, etc.
Rare might be limited to just 1 or 2 and might feature things like the ability to self-raise or to offer an additional charge to Swiftcast, Bloodbath, Second Wind, etc.Finally, Epic grade of materia that we might take only one of and which is specific to one's job in order to offer some simple change in power that nonetheless varies one's rotation at some scale.
Because these would be situational and either actively cast or conditional, they might not even take on AP themselves, but simply drain AP from the materia slotted below them upon use / if used. In that way, they come at cost, temporarily draining from one's dump-stat Materia with the amount trickling back to the drained Materia over time.
For instance, reducing the damage of Twin Snakes and Dragon Kick themselves in order to increase the modifier of Twin Snakes would allow for one to drop Twin Snakes before DK and TwS and thereby allow for different optimal GCD thresholds. By supporting only a few of these, with very simple rules in themselves despite decently pervasive rotational effects, the devs can allow for tweaks to playflow for jobs that would otherwise just barely fail to attract certain players without creating new balancing nightmares.
____________________Scrap the Materia system entirely and do something around AP instead. No firm idea what that'd look like yet, though. /shrug
I wouldn't mind that they're different sets... so long as they actually look different and if they would (again) have a noticeably different niche/fixture/impact in/on combat, much like back when those armor ranks were created (Lancer being a half-tank about as distinct in its kit and purpose from Pugilist as it was from Archer).
But, so long as homogeneity is to be the only path forward from here out, then, sure. Or even just have Maiming and Striking be the same gear (both "Striking"), but inexplicably look different on Dragoon, and Aiming and Scouting both merge into "Scouting"* but have Machinist, Bard, and maybe Dancer* look different (per old Aiming armor instead).
* All are Scout-y, but not all look like they aim. And Dancer as often seems to be better fit to the current sleeker/lighter/unencumbered Scouting aesthetic than the current Aiming aesthetic.
I just hate that despite previously significant differences, all three melee sub-roles are now treated as the same thing while the ranged sub-roles are not... and yet "melee" then is charged three times the amount of gear to deck out that role. All for the purposes of what now amounts only to gear bloat.
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I feel like the charge limitations would probably be plenty. (If we're blowing past Swift-Rezzes so early on as to be quite worried about the charge limitations on the speed/efficiency of PD rezzes, Brink of Death seems practically a given anyways.)