In EQ1 classic, sometimes people would shout out they where doing banking for people dragging around a lot of coin or races that could not get to a local bank. It would be nice if you could just play a banker / merchant / trader / deal cutter as a class.
edit add 5/4/2016 - granted this should probably be a Skill not a whole Class but the idea is groups would have a "utility slot" and non combat classes go into them. They are level limited but do things for the gamer and friends.