This idea was inspired by the "Super Villains in Door Missions" thread.
I suggested there that a "Villain Generator" might be possible to give us named opponents for our adventures. But something else occurred to me:
What if, say at the end of Character Creation process, you could check a box that essentially said "You have my permission to use this Character as an NPC for random mission generation."
So, it's definitely an "opt in" type situation. Worried about what mischief your character might get up to? Simply don't check the box.
You could have it match up with players by alignment, level, even theme. I would expect, though, that it wouldn't take the whole build, just the base costume and un-enhanced powerset.
This would save having to build the afore-mentioned generator. Instead the program just sifts through the list of "volunteers", sorts by some criteria and picks someone appropriate. Oh, and I assume it would look for Player Characters who were not logged on. This way, you could potentially even come up against one of your own characters!
Maybe you could get a little perk when you logged in if your character had been previously selected?
I think it would be fantastic to meet a player whose character I had met in a mission. Could lead to some awesome RP and excuses for mini PVP stuff, too.