This is honestly just a fundamental ff14 issue where so many jobs while leveling them just teach people how to play them wrong entirely because they hold vital kit until the final few levels.
For the sake of equality i'm going to assume that every job is obtained at level 50 because i don't want to deal with classes
Warrior: Berserk "wrong"-ness is nullified at level 70, the only thing that can really be said is Internal Release or whatever it's called meaning you can't double inner chaos at the start of your burst anymore
Paladin: At level 70, Holy Spirit is the highest damage GCD you have and you can use it to burst. This is no longer the case at level 76 with the Atonement Combo, and it becomes completely useless unbuffed at level 90.
Dark Knight: I don't have anything to say for this
Gunbreaker: Cartridge Management
Monk: Using Perfect Balance is actually a damage loss at level 50 because of the changes in dawntrail.
Dragoon: The combo just keeps getting longer.
Samurai: Tsubame-Gaeshi changes the flow of your combo substantially.
Reaper: Reaper is fucking gauge negative. Communio costing gauge and being usable early instead of being a forced finisher is harder for a newbie to pick up because they can just do literally the same as they did last time and oops no finisher.
Ninja: Here's a skill that lets you do a mudra for free! (much later) Here's a new mudra that only appears when you use that skill, it uses the same pattern as the mudra that is literally useless outside of deep dungeons! (also something about doton idk)
Viper: In opposition to Reaper, Ouroboros is actually handled well since the Offering Gauge gives you 5 charges instead of 4 when you reach level 96, in addition to the previous skills being in a sequential combo instead of "just press the other one lol".
White Mage: Cure 1, Bottom Text
Scholar: the barrier skill not getting its HoT effect until much later on
Astrologian: Benefic 1. Bottom Text
Sage: Toxicon in general
Bard: Song order changes for some reason
Dancer: I don't really have anything to say about this but giving you a button that gives you 50 gauge when it used to do something meaningless was a bad idea since it gives it raw instead of in a "Ready" effect like EVERYTHING ELSE EVER
Machinist: Hot Shot has a lower potency than Clean Shot when you get it meaning that it's better to use Reassemble on Clean Shot until you obtain Drill (yet another reason for Hot Shot to be returned to its pre-SHB state)
Red Mage: So many combo extentions. Also now Accelerate gives you another instantcast GCD.
Black Mage: BLM's rhythm doesn't change much but it's annoying that it takes until level 60 for you to get the real gameplay (Fire IV) instead of level 50. Also you have to be told how to use the AoE optimally because (High) Blizzard/Fire II are fucking jokes and Transpose Freeze Fire II Flare Flare is optimal.
Summoner: The higher level you are the less hardcasts you have for some fucking reason
Pictomancer: What you said about Starry Muse.