I really think they should just get rid of the "can only use x skill at x level" system since they will let you switch the skills as much as you want in the dungeon anyways. Like still give us the same number of slots but axe the arbitrary level restriction.
I didn't even notice that was a thing until the other day. I really just stick to crafting and summoner 90% of the time and that SMN itself only needs like 3 crosskills that you're only EXPECTED to have in ex trials and raids (raging strikes, swiftcast, and quelling) so I never even noticed the restriction until I got yelled at for not having protect in a low level dungeon the other day.