I agree completely, the Spy needs some love. But when you think of the world of Edge, at least to me, Smugglers and Bounty Hunters are the first two character archetypes that come to mind.
And what is the very first thing we ever learned about the Rebellion? They have Spies that stole some plans.
The correlation of iconic careers being last is my feeling for why the Spy might not be getting the love it needs until later...