They add more equipment.
They add more glamour plates and dresser space.

They add more items in general.
They give us the chocobo saddle bag.

They're pretty good about being accommodating. But there are some places that don't ever seem to grow with the game.
For example, the favorite space for mounts and minions hasn't increased either.

I'm with you OP, this is a QOL change I'd welcome.
To push the concept a but further, I'd really dig it if we could save playlists the way we can have multiple glamour plates.
Even just being able to save 3 playlists would be super slick.