I know that destiny is ridiculed for having so much horde mode, but why not actually throw a 4-man fireteam horde mode in? Every 5 waves we have an option of whether to progress with the mission, or to take the reward and split. Got the idea from warframe, but destiny could easily do it just as well or even better. I'm sure it would bring more people back to the game. Especially with the chance to get a legendary engram or exotic piece on wave 20+! (Difficulty raising each wave)