Major spoilers ahead, proceed with caution.
Kyzrati has been posting a blog series about how to weave a plot into a roguelike/procedurally generated game. It's definitely worth a read.
Part 1:
http://www.gridsagegames.com/blog/2016/10/weaving-narratives-procedural-worlds-part-1-value/Part 2:
http://www.gridsagegames.com/blog/2016/11/weaving-narratives-into-procedural-worlds-part-2-characteristics/In part two, he posted a fascinating graph:
This graph depicts every major NPC in the game; where you can find them; their faction; and the impact they have on future events/other NPCs. Or as Kyrzrati put it, the "major NPC encounter visualization ... showing those with a direct effect on some later encounter (arrows), as well as those with a relatively significant long-term impact on gameplay (bracketed length)."
Let's try to decipher it! I haven't thoroughly explored Testing, Armory, or Quarantine so I'm not well versed in the plot events in there. People who have seen more of the end game will probably have a much better idea than me about who some of these dots could be.
First off, assuming I am not colorblind, we have 8 majors factions. Interesting and more than I expected.
The first one is the easiest. The red dot on the left is revision 17, since that's the only early game NPC. What about the other two red dots? I believe the middle is O7 and the third is revision 17 again in Archives. I'm not the biggest lore/branch junkie though so correct me if I'm wrong!
The lime green one is probably data miner. You encounter him early and he can potentially change the rest of the game. Fits the bill. Interestingly, if I'm right that means Data Miner is not partied with the other factions. No other lime green dots.
I believe orange is Zhirov's faction. The orange dot on the far left is probably O8, who can be found in Zion and gives you that hack to summon help when needed. Two of the central orange dots are Zhirov himself, representing that he can be found in archives or the caves. The far right orange is Zhirov again, since he can show up in access under certain conditions. If I'm right that Zhirov = orange, there's one orange dot I can't account for.
Note that one of the oranges links to black. If I recall correctly, Zhirov gives you a Main.C related hack... perhaps black is Main.C itself?
There's a free floating yellow dude. No idea who that is. Could be O7 if some of my assumptions are wrong.
Warlord is either light yellow or purple. I suspect purple, since that would allow one of the other purples to be God Mode. I have no idea who the other purples are and no idea who the light yellow is.
No idea who light blue is.
Finally, it's worth noting that the branch off of Zion is locked. I bet there's a major NPC in there that no one has seen yet.
Lots of robots still to meet (and blow up).