Let me just say, I really dislike world pvp. Or maybe that's not the way to put it, actually what I really dislike is ganking. I think pvp can be fun but killing low leveled players just for the reason of ruining their gameplay is not my cup of tea. I don't gank people and I really don't like being ganked.
"Just don't play on a pvp-server" you think, and yes that is the way I have solved this problem. Unfortunately, before I realized how dreadful world-pvp (i.e ganking) could be I started a main together with some friends on a pvp-server. After leveling that char I decided I'd never go through that hell again and so I am staying away from pvp-servers from now on.
But I think there must be a way to solve this. I know many people think it's worth being ganked a couple of times for the possibility of doing it themselves to some poor lowbie. But honestly I don't care what they think, those are the people I don't like - I even tell my ganking friends that they're bastards and I never feel sorry for someone who's being ganked if I know they're doing it themselves. Setting them people and their opinions aside, and I do, I think there should be some system that prevents ganking. Ganking should actually be punished. The no-honor gain is clearly doing nothing. I'm not peace-loving, I am lazy. I do not like to get my game interrupted because someone is bored.
I have thought of many things that could change this, some are easy solutions and some less easy. One thought would be that if a char is grey to you, you can't attack him. But what about if the grey person attacks you first? Well that's another things of course. It would be like a semi-non pvp server. You can still attack green/yellow/red colored chars all you like, but the real low ones are off limit.
Or maybe a diminishing returns on kills? When you've killed the same person 3...4...5 times they become immune to your attacks for an hour or so.
How about a debuff on the ganker? For every grey player you kill you lose 10% stats for an hour or two.
And they really should have those sanctuary areas extended to the entrances of instances. So the area between the summon stone and the instance portal is a no-kill zone. Yeah that's a great idea.
Just some fast thoughts, I'll probably come up with more.