Topics touched upon included the Esper's healing ability (the devs claim the class is "the best single-target healer" in the game), the lack of movement speed reduction while casting, its high burst damage potential in PvP, and that nifty Phantasmal Armor skill that was seen at the end of the re-reveal video.
One fan asked if the Esper could be built as a pet class. "You also have the ability to focus yourself on a pet build," a developer confirmed. "Last week my build was based around Phantom Swarm (three small illusionary pets) and Geist (one large illusionary pet). I had tiered these guys up as much as I could so that they were doing tons of damage, healing me at the same time, and blowing up on their deaths to do AoE damage."