Yet Another Mode
Currently, Overwatch has four modes, not counting Competitive: Assault, Escort, Arcade, and Control. (Hybrid mode doesn’t count because it’s literally mashing the former two together.) There’s also the weekly Brawls which certainly spice things up, plus the holiday modes, so another mode couldn’t hurt to mix things up. Even if it’s just for a while, a new mode would help liven things up in some capacity.
Exactly what Blizzard could do is sort of up in the air; those mad geniuses could come up with anything and still blow us away. It could be a hybrid of the Halloween horde mode and Escort, or it could be selecting the most popular custom game and letting it run for everybody for a week or two. Each map in the game has a specific mode tied to it, and since the tease is relating to King’s Row, there could theoretically a brand new mode related to it and only it. Maybe they’re planning on adding modes for specific maps?
Given that the newest Overwatch comic is focused on the titular group heading to London to deal with a hostage situation, perhaps that could be the new mode? One team goes for AI hostages, while the other group is Omnic versions of other characters and has to stop them? Think less “escort mission” and more Capture the Flag; once a player gets near them, they have the hostage and just have to make it to the designated safe zone.