How many loose ends does your campaign have trailing behind the PCs? I have only been running my face to face game for a few years now, playing maybe 40 hrs a year or so and yet already there is a trail of loose ends, uncompleted quests and unsolved mysteries.
I have intentionally set up two concurrent story arcs. The point of having two is that I don’t want the campaign to feel linear or railroaded. One plot often interferes with progress in the other and the inter-weaved stories are richer and more complicated than a single story.
On the other hand too many loose ends do not add to the overall story, in my opinion. I think that too many loose ends can leave the players feeling frustrated and for the GM more balls to keep in the air if he is to keep tabs on every loose end.
Something I learned from solo rpgs is to keep a log of plot lines or more accurately loose ends. This simple technique first of all made it blatantly obvious how many loose ends there were. It also made it pretty easy to plot in mopping up these loose ends as I prepped future sessions. I am not saying that you have to nicely clean up every loose end in the very next session but when an opportunity presents itself it can be very fulfilling for the players to finally track down loose end.
For the GM it can also mean less work. Why create a new assassin when there is one in the characters’ history already? My player characters are hanging around a 50 mile radius area and bringing people back into the story is pretty easy right now.
It isn’t just me that says keep the total story lines count down. Look at classic sci fi and fantasy TV series and although you may get a different adventure every week you rarely ever get more than one over arching story arc that spans from episode to episode.
I have no idea if there is an optimal number of story arcs to have in a game but I bet it is more than one would expect. When I started thinking about this I thought the right answer is two but that I think is way too low a number.
Firstly one needs the main campaign plot. I also think you should have a side plot to stop it all becoming to linear as I mentioned above. Each PC should probably have a story arc that comes from their character background and I would say that each character should be able to spawn their own story arcs, most PCs do not start out wanting to become a lich lord or whatever but the GM should be be able to accommodate those that are compatible with the game.
I make that two story arcs for each player and the campaign. That also fits with that is happening in my campaign now. Or to be more exact, I have more than the twelve (five PCs and the campaign times two) story lines and loose ends and that is why things seem somewhat crowded and my players often forget who did what to whom and why.
The forgetfulness could be middle age but having too many plots, NPCs and clues floating around certainly doesn’t help.
That’s fairly close to what I run, but I’d also suggest genre plays a role as well. I’ll sometimes have a party arc running as well in games where there might be one (in other words, a frontier-based game might have someone looking for that “pack o’ varmints” that foiled a robbery), but for other genres that doesn’t work as well. But I always try to bring a character’s background into an arc as well. That’s something I think some GMs overlook, and it tends to hurt player engagement (at least in my view).
I cannot wait to see some of your modern day stuff that you keep hinting at.
Left to my own devices, I would probably create many different optional plot threads that could be followed. Probably too many.