Mission architect -- an amazing system that allows a very creative player-base to finally take the reigns of creation and make amazing in-game arcs that feature personalized stories, personalized characters, farming, well made.... wait, what?
Yes, you heard that right, people have already began to leverage City of Heroes's architect system into nothing more than powerleveling tool, and the community doesn't find that to be too enjoyable. Luckily, Matt "Positron" Miller, the lead designer, has already stepped up with a post to the community on the City of Heroes message board about how they plan on dealing with these problems.
The team wishes to remove the rewards some characters may have gained through powerleveling, all the way up to removing access to characters that were solely leveled up via mission architect exploits. Past working on a player by player bases, some badges will be changed while others may be removed entirely due to the exploiting groups surrounding them. Lastly, but certainly not least, the team will be proactively banning missions that are created to exploit the system.
For Matt's full plan, check out his post over on the City of Heroes message board.