Repeatable Quests/Questgiver NPCs

It would be nice to be able to flag an NPC as a quest giver and for what type of quest, both to help with pacing, but also set up things like repeatable quests. For example, the thieves guild master could be set up to repeatedly give quests about only jobs related to the thieves guild and theft, while you could set up a repeating quest with the captain of the town guard to patrol the area and hunt monsters.