Here's what I'm imagining. Each race and faction has their own subset of abilities and such that could probably be made into their own subclasses. [b]Awoken[/b] could definitely have a subclass of their own, revolving around non-elemental space magic. [b]Exos[/b] could have a subclass revolving around their robotic nature, possibly being similar to the tech-powers from Mass Effect. Not sure what [b]Humans[/b] could have (maybe elemental magic revolving around the Earth element?). Here's where I think it could get interesting. We've encountered a whole slew of enemy factions and races, and I think that there's some amazing potential for new abilities and subclasses here. Obviously, not all enemy types would be playable (Guardian Harpy? That'd be ridiculous), but I think there would be enough there for one or two from each faction. [b]Fallen[/b] could have Vandal and possibly Captain guardians. [b]Vandals[/b] could be restricted to the Hunter class, and their exclusive subclass would involve cloaking and the use of Arc-based attacks. The super could involve the use of a sniper. [b]Captains[/b] could be Titans, and their exclusive subclass would render them able to summon Shanks to assist them in combat, as well as the ability to summon a Scorch/Shock/Null Cannon. [b]Vex[/b] could have [b]Hobgoblin[/b] Hunters, with their subclass revolving around time manipulation, and being able to freeze enemies in place. [b]Cabal Psions[/b] would make good Warlocks, and their subclass would make use of their psychic abilities. [b]Hive[/b] could have Knights as Titans, and maybe Acolytes as Warlocks (they could have the turret ability from their Taken counterparts).