Perhaps I'm approaching this from the wrong point of view, but it seems as though that the problem that you're describing is more with the people than it is with the system.
As it is, traders are offered no real protection outside of level restrictions and that they cannot be destroyed prior to a demand being placed upon them; be it tax or dropping their cargo.
If a player is going to grind his or her way to level 81 without ever having engaged in enough social interaction as to understand how to open a simple trade window, that's on them. But I would dare propose that allowing certain factions free reign wouldn't curtail that attitude of quasi isolationism. If anything it would simply attract a similar class of player who would be more than enthused at the prospect of simply destroying without care or concern, which is an issue that crops up from time to time within the Xenos.
I do know that you mean though, and where you're coming from. Today either alone or with a friend I engaged at least nine transports. Of those nine only -one- complied with the request that they drop their cargo, and it was that same one that actually responded in any way to the red hot RP hotness that I was tossing their way whilst typing with one hand soaring through asteroids after cruise attempting trains.
That one who complied then came back later on with intent to make us explode.
But, yes, people would rather logout/run over and over again or simply type 'pls:)' ad nausea than dare open their chatbox for two moments and throw a bit of substance in there (other than a stream of PMs).
But I'm not sure that simply blowing them up at every opportunity would solve that.
