I'm not sure if this has been suggested before, but and idea that sprang to mind enough for me to come to the forums and actually make an account to spread is thus.
What if instead of receiving a piece of gear for a job when you purchase it with tomes / obtain it from books / drops, you instead received a character bound reward item that allowed you to purchase said slot of said gear for all jobs?
Say you roll and obtain a chest piece from savage, you then use the chest piece item and go to the vendor to claim a chest piece for all of the jobs.
I understand the issue then becomes people not wanting to do savage once they've obtained a full set of gear, but honestly if the game is supposed to support one player having every job, I don't see why this hasn't been the system we've been working with the whole time in the first place.