Snow_Globe's post has reminded me of something I've wanted since it occured to me. The ability to go back with any character and complete story arcs that you have outlevelled.
I think the best way to accomplish this would be to have the character auto-exemplar'ed to the maximum level for the arc. A warning would be displayed to alert you to the exemplar status in the NPC dialogue window before you pick up the mission.
Something like: "You have exceeded the maximum security level for this mission. If you choose to accept this mission, you will be set to the maximum security level until the mission is cleared."
It'd be a great way for people to clear debt or earn influence while getting to enjoy the game's stoylines without worrying about outlevelling their contacts.
I love running in full teams, but you can't experience everything the game has to offer like that. Unless, of course, you lead the team and refuse to do anyone else's missions. Solo'ing works, too, but it's not terribly exciting.
