Cool, yeah the Druid is easier to intuit, and in my game it's more story than efficiency.  I can also see the Green Lighting Bolt wizard discovering Rage as a "kind of magic" as not Oliver Queen, but the band Queen would say, embrace a path taught to them and maybe even return it and both figuratively and literally flip the table at their magic academy.  This could lead to a conflagration of Rage Magic that will make the Wild Magic of the spell plague seem like a hiccup to the order of the things.