Minions/Side-characters/etc play an important part of many story-related Missions: Quinn, Riot Alice, Vallus Smokemane, The Charr's Sparing Partner, Pol, and many more play an integral part of your story...then are never heard again. Of course, a simple way of doing that is to simply introduce a character and then have them killed, but that's lazy writing 101 (and, in my opinion, done far too much in GW2...). While some of the story characters die or not (depending on your actions), it feels odd to just leave them behind, never mentioning them again or interacting with them again...
As you progress in game, you gain more and more power, so that brings up a brief question: What if there was a Hireling-Style mini-game that involved these characters. My thoughts more-so revolve around Assassin's Creed Brotherhood, where you had control over a small brigade of randomly generated underlings who would go on missions that, while minor compared to the main characters, were still integral in the success of the overall mission. Creating Trade Deals, managing defenses, assassinating minor lieutenants, all the things that were typically attributed to luck or minor background events.
Story-Based Hirelings of course would have plot armor and would simply "Pull back, injured" for a certain amount of time if a plan failed, but random NPCs could be killed off if they failed bad enough.
No idea what rewards for this sort of thing would be. Perhaps "resource points" or some other aspect that could be spent on trinkets, doodads, and other resources.
The idea seems fitting for the "Commander", especially given that he/she is already attempting to make a group throught the story. For the Charr, they would start out with their warband. Asura have a Krewe. Norn have Hunting parities or such. The Humans work for the Queen. And Sylvari? I actually don't know on that...
As a side note: I am aware of the "Time" and "Resource" aspect of implementing this idea, and understand how very unlikely it is to ever occur. God knows the programming would be a nightmare. However, I still view it as an interesting "What if" scenario.
Minor Edit: I accidentally said Assassin's Creed II instead of Assassin's Creed Brotherhood. Sorry about that.