Solo missions that are incredibly hard and long. You can leave and resume from the last checkpoint like story missions and raids. Once you complete the mission, you are rewarded an item or items such as an exotic weapon 100% guaranteed. Replays will award lesser but useful items. What I have in mind is a long and incredibly difficult solo mission that requires extreme use of your intellect. Stealth tactics would be nice as well (too bad the current game's mechanics do not support this, besides the Gorgon's Labyrinth). Here's a mission example: -Assume the role as a civilian -Find leads of a Trinary Star spy group posing as civilians in the City -Report to the Speaker of your discoveries (done by the character's mic and technology stuff, so you don't have to go all the way back to the Tower) -Shadow a Trinary Star suspect -Confirm the suspect is a cult member -Report to the Speaker of your discoveries -Enter the City's security system to find the suspect's activities -Deduce the suspect's group's location -Survey the area -Confirm the location is a Trinary Star spy group location -Trigger a false intrusion alarm to evacuate the spy group and surrounding civilians -Use an EMP to terminate cameras in the group's base -(Playing as your Ghost) Scan the area -Find hidden items immune to the Ghost's scan -Scan the hidden items -Report to the Speaker of Trinary Star's plans -Arrest the Trinary Star suspects -Interrogate the suspects (using high-tech lie detectors and stuff) -Report to the Speaker of another Trinary Star hideout -Command the task force (draw a plan for a task force to invade the hideout) -Retrieve the Dark superweapons -Interrogate the Trinary Star suspects -Kill the Trinary Star suspects (muahahahaha) -Assassinate the Trinary Star majors in secrecy -Massacre Trinary Star members in their third hideout in the City in secrecy -Find the Trinary Star leader, hiding your Guardian status -Confront Crow And after a bunch of stuff, you return to the Speaker to receive a reward. And this is taking things way too far and off topic, but I want to type them anyway. -Defend against the Speaker's task force -Interrogate a surviving task force member -Kill the survivors -Follow Crow -Remove evidence of your identity The plot twist doesn't seem that epic and goes against the idea of replayability so just ignore it.