There's a lot I agree with you, but I personally believe that the fact there's no reason to PvP besides for the fun of it IS part of the problem, because that kind of PvP lacks context. Frontier has gone to a lot of trouble creating a Universe where the Pilots Federation fight the shadow wars of the various factions in Human Space, from the cold war between the Empire and the Federation, to two mega-corporations taking the concept of "hostile take-over" to a whole new level. It is only natural for some players to choose a side, and then want to face players on the opposite side of the fence.
It is that lack of context that, in part, creates a perception of griefing... even if in the attacker's mind they're attacking a legitimate target. It's also why when I go marauding, I'm careful to establish context, even if it means someone might get away. It is also the reason why I enjoyed the PvP encounters I had in Powerplay, even if I didn't enjoy the ways to earn merits: those hostile encounters I had with other players had context. I knew why they were attacking me, and they knew why I was in the system. Even if we didn't exchange words, the fact that we were pledged to opposing sides, and knew it, made all the difference.
It is why any proposal I have to enhance PvP starts with allowing players to pledge allegiance to a faction, whether its a minor faction or a Superpower (or declare themselves a pirate.) I would also add the option to declare enmity towards a faction as well. Even if nothing else comes of it, besides flagging other players (and NPCs, for the PvE crowd) as hostile to you, I think it would go a long way towards reducing the perceived amount of griefing in Open.
I mean, which scenario* is better:
"You're making a supply run for the People's Congress of ABC123, a Federation faction that's in charge. As you're flying along, an unknown Pilots' Federation ship approaches you from behind. You have no idea why they're there: they may be moving to attack you, or they could be simply traveling in the same direction. Suddenly, an interdiction tether engulfs your ship. You still don't know what's going on: are they pirates who can be appeased with your cargo? Are they someone who supports the Imperial Party of ABC123? Are they some murder hobo who just wants to kill you for the LOLs? You don't know, and that lack of knowledge causes you to delay several seconds, as the possibilities run through your head. By the time you react, you're already under fire. Ten seconds later, you're dead."
or
"You're making a supply run for the People's Congress for ABC123, a Federation Faction that's in charge. Suddenly, a Pilots' Federation ship, glowing in a malevolent red on your scanner and HUD, approaches you from behind. You instantly start to take evasive action, because you know they're after you. As you try to keep them off your six, you select them, in an effort to identify them. You see they're supporters of the Imperial Party of ABC123, who have been rising in influence over the last two weeks. You now know if they catch you, they'll try to kill you, so you better make sure they don't catch you."
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* With the usual caveat: players are still allowed to play in the mode that suits them best, and there are no bonuses or penalties for choosing one mode over another.
