I start thinking about you can encounter with a NPC group instead of only a single one,
but unlike the random NPC, the one you’re found, has it’s own rules to running the group, such as a travel merchants with it’s own type stuffs and few hire guns on the road, you may going to trade a few item on them, or you can simplely attacking them, and loot any good stuff,
or you can see a bunch raider on the road, who will instantly attack you without or with any reason, some of them may even not be a hostility on the first time, and will threaten you for it’s own benefit, such as pay the trespassing, and you may even try to convince them to letting you go, or refuse and start fighting,
there can also found a mercenary with a few high skill whichs you can pay them to recruiting them,
or even slaver, that you may consider buy some slaves with a poor skill but very cheap,
Mabye the dead groups became alive too! the survived scientist group and military group,
and mabye you can even seen the gang fight really happening! whichs a two group who will fight each other, with lot drugs and guns, baseball bat, knife, or something like that.