Just an idea here take it or leave it. Have a recurring monthly event that arrives similar to xur, random location on random planet. Give us an event that excites us about defending our last city. Here is my idea. A call to arms 1. A bounty or bounties issued from the vanguard to find and eliminate the incoming threat. The vanguard will have become aware of an incoming threat and it is our job to find and eliminate this threat. Each month would be different. For example a cabal ship crashes into the cosmodrome somewhere in order for them to establish a foothold on earth in attempt to coordinate an attack on the city. 2. Location will be unkown. Set patrol to a 6 man fire team and we have to explore locations and find out what the threat is and as a team eliminate said targets. 3 upon completeion of eliminating the threat the bounty is complete and turn in to the vanguard. We then get rewarded with worthwhile loot 300-320 for our defense of the last city. Just a quick idea i had feel free to expand or criticize.