I've dropped none. I can't seem to find any new ones.
What I couldn't complete is Chapter 3 in the story, which has not been finished by the developers either. I'm Level 6 Notoriety and have looked all over for new people(and old) to give me some new quests, sadly haven't found any. Maybe I need a high level before I do though...it's just bother some to run around over and over again(which is nessecary I know!)
Can I ask, who have you spoken to get these requests, please?