Just an idea, and I'll keep it brief: Horde mode. It's been done in games such as Halo and Gears of War. A wave based mode also serves as the multiplayer of Mass Effect 3 if I'm not mistaken. Either way, the point is, endless waves on various maps where a fire teams of 3 or 6. I'd prefer six as it gives you an excuse to team up with more people and helps practice raid survivability and gives raid groups more to do. Could even consider larger groups if Bungie ever wants to get crazy with the numbers, but ideally, a raid size team must stay alive as long as possible. No reviving from downs or limit the number of downs they have. The longer you live, the better engrams, gear, marks, or w.e you're eligible for. Same for different difficulties. Could also have bounties for it. I wouldn't imagine that it would be too difficult to implement. Gears of War 2 (not sure about 3) used it on PVP maps; could do the same, use locked in areas of PVE zones, or even create new maps. Although there are glaring issues that need to be fixed, this type of mode could keep PVE players busy while they wait for new content. It's also a good way to utilize matchmaking and build cohesion among players besides the raid since you can only do that once a week. Plus, adding in new maps, different enemy waves, mini bosses, etc. can allow it to function like public events in a zoned area, allowing the matches to at least feel different as the waves persist. TL;DR: Horde mode for the win. At least think about it. Could use PVP maps with PVE enemy spawners, locked in PVE zones, or new maps altogether. Preferably raid size groups, or, perhaps use whatever size players can make it through with (1-6), and see how many waves they can survive. More details above, but loot would be based off difficulty level and number of waves survived. Could even have a leader board.