XI kindda had this in the form of Scholar

played correctly sch could switch from heals to nukes, buff and debuff, spread one target spells to multiple targes and give stat bonuses. Granted there were no items uses like ppl have been suggesting but sch imo was the most active and versitile mage in xi. I think the only reason it gets the poopoo from players is because it was also one of the more complicated and gear heavy jobs, which also made it more exciting and prevented boredom from seeping in too much. I loved sch and would love to see it reappear xiv style