Animations I'd change...

NIN running/jumping/idle animations. Put them back to Rogue ones which are like, 1000x cooler and infinitely less weeby. At least as an option!

SMN/SCH running/sprinting animations. Normally, I like to use the toggle to keep weapons unsheathed while doing a dungeon and the like (Since, logically, it wouldn't make sense to sheathe your weapon while in the middle of say, an Imperial base or a monster infested dungeon) but my gosh are the animations with the book out just dire, to the point where I explicitly manually sheathe them to spare my eyes. (Also, it would be neat if these 2 classes got some diversity in animations across the board with stuff like running and idling. Kind of like how BLM and WHM have distinct animations for their same weapon)

BRD Peloton animation. Okay, the class is focused around songs and playing the harp (Bow). Where tf are they pulling this flute/whistle/piccolo/recorder thing from? I get it for the Performance stuff, where you can say they'd literally go and bring a particular instrument for the occasion. But with Peloton? They randomly bring out an entirely new instrument that sees no use in literally any other part of their kit... On the flip side, MCH's makes total sense, pressing a button on their Aetherotransformer. Simple, sensible, effective. (If somewhat limiting to glamour because having an interaction with it means that many people's wish of being able to hide it is less feasible because then the animation would be very odd)

DRG's Chaos Thrust. "Lemme just slash at you with this thrusting weapon". Heck, it feels as though FFXIV's single damage number for an attack is how this attack would be shown if it put up a damage number per swing of an attack... 0, 0, oh now you've stabbed them with your spear, here's actual damage >.>