Your opening paragraph is very interesting as it highlights the different kinds of multiplayer mindsets that are at play. In most games where players are pitted against other players, there's an equal objective for both parties to aim for. Like you say, it could be a capture the flag scenario, or earn points for your team.
But when it comes to acts of piracy in the multiplayer setting, there's nothing in it for the trader except maybe a little anxiety and the lure of risk that few crave. But what does he really gain? Nothing really. The game takes care of the justice, which the dead trader may or may not ever hear about.
A while ago I made a suggestion in the game-play and ideas forum that somehow those on the end of a piracy encounter needed to become more activity involved in the whole scenario and subsequent outcome - and not just be another faceless bit part character/victim in the glorious life and times of notorious pirate x.
No, the trader could be given a more active role once the dust has settled and he's back in the station receiving his insurance payout. I suggested that a victim of piracy has the option to contact some sort of npc intelligence network agency and be given exclusive tracking rights on the person that killed him (for a set period of time). The trader now has something that opens up all sorts of avenues for him to go down. He can use that tracking right to exact personal revenge. He could sell that tracking right to a bounty hunter, who on successful completion of an assassination will receive the bounty - and crucially instead of the pirate paying fines (as currently planned), instead he pays compensation to the trader who issued the tracking right. And finally, since the pirate would never know who the trader plans to sell a tracking right against him too, or its expiration date, the pirate may even contact his victim and buy the right himself, just to have it off his back (it would be annulled).
So it doesn't necessarily alleviate any anguish one experiences when being a victim to an act of piracy, but it does make the victim become an integral player in any subsequent after events should he so chose to. He effectively gets the satisfaction of holding all the cards for a set period of time. I think that's a better way of leveling the playing field so that multiplayer encounters of this kind are no longer emotionally one sided, the predator can become the prey, and the victim the victor, should a set of followup circumstances fall into place.
I think tracking rights would also bring bounty hunters actively into the loop and give them something tangible to use to hunt down specific targets instead of relying on random encounters. Whole scenarios of revenge and retribution can spring up here and create a whole market of interaction between traders, pirates, and bounty hunters.
But the crux of the matter is a mechanism is in place to give some power back to the victim. Whether the victim chooses to use it is their personal choice. Also worth bearing in mind these rights could be used to track the Radiant Dawn's too - i.e. infamous npcs with juicy bounties (but that's beside the point!)
I like this muchly.