More Iconic Final Fantasy Costumes/weapon glamours:
More glamour from other Final Fantasy game's main characters (FFXII, FFIII, FFX-2)

Final Fantasy Remake collaboration
I am still puzzled why the almighty Sephiroth has yet to make an appearance as an alliance raid/trial boss yet.

Motion Change
Much like emotes, motion changes could allow players to swap their animations with other animations from other final fantasy games. Like rouge could swap their battle stance and basic attack animations with Rikku from FFX-II, or Dark Knights could swap their animations with Auron from FFX. Would allow much diversity for players and allow for more dynamic photo shoots. Each motion change would be class specific and could be given it's own sub-menu for customization and linking to gearsets.

Glamour Dresser Expansion
Increase size of Glamour Dresser from 400 to 600 or 800?