ok, that's an idea I've had for quite some time, I worked a bit on it, so now I'll talk about it.
First, that's NOT a campaign, that's something to be used by campaign makers.
The original idea is: I'm fed up with all those pirate factions using old GTVA ships. Please raise the hand those who haven't seen pirates flying in Loki or similar ships?
So what is that scavenger thinguy?
To sum up: scavengers are terran and vasudans ( and even whetever sentient species of the same tech level you could have in your campaign, that would fit in the concept ) outcasts that live in crappy stations or large "dumping-ships". They're lurkers, "scavenging" ship parts from areas where a battle occured recently, or stealing stuff from civilian stations, occasionally acting as pirates too when times are tough. The main interest is that they also act as hired guns or mercenaries. They will work for anybody who can afford them ( they're cheap, coz they're not elite troops or anything ). They have no access to GTVA or any real faction's blueprints, and even if sometimes they can steal a ship, reverse engineering isn't something everybody can do ( and scavengers can't, to say it bluntly ). So they make their own ships, that are average to the best, but cheap.
I would make a full scavenger fleet, which does not, of course, follow the GTVA designations, so it would be something like:
scout ( very light fighter )
fighter ( well, fighter

)
gunship ( a mix between a bomber and an heavy fighter )
and various capships, which are not really meant to be used for combat ( but ships like dumping-ships can be really large, gaining additional sections as they age, leading to strange things ).
They have reasonably low power weapons, too ( those guys can't be ubber powerfull ).
To sum up, they're not a faction that would have any power on anything, they're just troublemakers that will help anybody who pays them.
Now, where YOU come into play: I'm not going to do that for nuts, obviously. I want to know if you're gonna use them. I'm quite ambitious on this thing and, being the arrogant french I am, I fancy those guys to be aknowledge by the community as a real part of the FS universe, as they're described above. The fact that they have no real incidence on any military or political issues ( they just provide easy canon fodder, to be blunt ) should help it.
That's why I'm asking you first, coz I'm not gonna waste my time on something nobody will care about.
voila, it's all up to you.