I feel like the simplest option would be just to stop giving skills besides traits that change exiting ones, as the Devs would inevitably have to remove old skills from older job no matter how bloated it already is just to have something to give at the higher levels.

Actually I would actually propose compressing the skillsets to level 1-60 and then focusing on the traits moving forward, that would give players a sense of progression while also giving them time (61-90 or 100) to perfect their rotations. From there the max level cap would not be increased until an Abyssea analogue should one such xpac exist.

I would also consolidate the combos and proccable attacks (Straight Shot/Refulgent Arrow. Windmill, Bloodshower, etc) , into a single button to give the devs somemore room where applicable for new skills.

(for the Dance moves on Dancers, the Green and Yellow ones would be moved to the AoE attacks the latter's icons would change color to reflect this, and the basic combo would not be consolidated in favor of having them change into the attacks they proc instead. Likewise the proc'd attacks' icons would change colors to match the respective dance moves of the attacks that would proc them)