So the idea is to add out post to each planet including Earth this way it will seem as if we are gaining ground story wise and possibly open up new map areas. These outpost will add quest origin and destination point's and when connected to fations such as future war cult and dead orbit will make these factions more relevant. Quest can be implemented in the form of delivery quest and escort quest, how does defending a caravan from vandals and a swarm of dreg trying to prove themselves worthy sound ? With these new outpost comes the option to defend these out post from enemy attack. The defensive missions can be activated different ways. One way would be to visit the outpost and take a guard mode which would have you and a fire team defend the out post from both it's walls and the field outside the out post out post would be equipped with turrets and mortar launchers but the enemy would be able to disable these weapons. This also opens up the options for new enemy types based on siege tactics (something large and ugly with way to many legs that poops out thrall, think very large oger/catipillar hybrid with a hole its lower stomach for thrall delivery). There could also be a random public event where you receive a distress call from the outpost and have a limited amount of time to reach it and begin the defense.
This could also be a way to finally get your sparrow races I see having to get from the tower gates to the outpost or from outpost to a camp with a delivery before the other guardian does. This could be done in team's (relay race ?)or solo.
Even the iron lords could get in on since the crucible and iron banner are there to prepare guardian's. These outpost could also add a new stage for pvp and new game modes. King of the hill, capture the flag, and tower defense.
Stay tuned like and follow I'll be adding more later !