While I'm all for giving jobs more unique flavour, especially when it comes to tanks who have a ton of role abilities. Role skills themselves do serve a purpose. They provide early game players a sense of growth that can be felt when synced. Job/class skills don't sync down, but Role skills do.
By all means limit them to skills that, by mid-end game are niche and common, but like, Reprisal and Rampart could afford to be divvied up between the tanks again and nothing would be lost.