I just wondered about increasing my faction cap for the kurzick and went to speak to the appropriate NPC in game.
When you click on ways to increase the cap, it lists every way there is in game, however i cannot remember at all which ones i have done on in terms of the challenge missions.
I propose theres a way of gettin him to just list the ones your yet to do, its nothing major and hopefully an update would work retroactivly. Its that exactly an important change but still it could make the rewards NPC a bit more polished.
Improving NPC [Faction Rewards]
BenjZee
MithranArkanere
They do already. Ask them how to increase your cap. They'll list what else you can do.
Abelard
Actually, he already does only list the things you have left to do.