I have an idea on a way to alleviate the storyline problem thats a mixture of things I've seen on this post.
I think every zone should have a new contact added (or maybe they can use the existing detectives/brokers), that will give out a repeatable storyline arc. Have the level range for this arc be the same as the newspaper/policeband missions in the given zone. This storyline arc will be equivalent in length to other story arcs in the zone only with one bonus, when the missions are first accepted it flags everyone in the team with the mission arc status, causing the auto-exemp from TF's to kick in for higher levels.
It sounds a lot like TF's, but this would be doable whether you were solo or in a group of 7/8, giving all possible group arrangements the ability to get recipes. If coming up with storylines for the new arcs are a problem, then they could simply repeat arcs currently available in that zone. For example at level 15-19, one of the repeatable arcs could be "Dr. Vahzilok is at it again", and you repeat the Vahz story arc.
Hopefully these would be made smaller than normal TF's for those who don't have a ton of time, but since you can do them by yourself, it wouldn't matter if it took you multiple log in's/outs to complete them. That would alleviate the current problem with the story arc drop issue, the fact that it's non repeatable except for rolling new characters.
