If you think about it, the amount of newbs killed in the starter zones by Veterans is a very good indicator for balancing the penalty system.
The devs can define a number, that mirrors their imagination how dangerous the world should be.
If the number of newbs killed by veterans is higher than this number per month, increase penalties.
If it's equal, perfect.
If it's lower, reduce the penalties
Increasing penalties doesn't work. All it did was force people to be murder hobos if they want to PvP. Once you are a murder hobo you kill everyone because there is no longer a limit to not kill players.
How the community works is that after the patch to remove risar head rep gameplay loop, most of them waited or burned up the remaining rep they had while waiting to see what SV would do about the problem.
Players were very wary about using their precious rep on noobs which would be a poor quality of PvP per rep lost.
After SV pretty much said no more risar rep and didnt fix the situation after the following patch people let go of their rep and a lot of people went neg rep.
Now since losing rep does not matter because you are already negative and will not be getting out of that status the killing of new player has risen drastically once players figured out that this will be the norm for the while.
The solution has backfired. And increasing penalties for people winning at a PvP game would probably just make the situation worse up untill you just make PvP improbably in this PvP game. At that time you will just see people quit playing and you will lose a huge amount of your players. Some players who are too worried to lose rep have just stopped playing because for them the threshold of being too punishing has already been crossed.
There's lots of issues with this game that would lead to noobs being killed repeatedly not just tied to reputation. But having a carrot and stick approach is usually the best approach to getting the behavior you want. Just punishing more and more to double down on something so far has been disastrous and made a worse game.
The things that lead to noobs being kill. Its not even because of people are actively going out to kill noobs to get back at SV, its because the current system forces people who want to PvP into this.
Towns are hubs -
If you want to PvP that means you need to find people. Where are you most likely going to find people at towns. Where are you able to fight? Right outside gaurdzone. In this giant world people only fight right outside towns.
Now whats right outside of towns and draws players? GraveYards.
Where do noobs go to start out? Graveyards.
So naturally players are drawn to towns and further drawn to the graveyards. Other locations around town that draw PvP are stables and crusher/grinders. Since they are usually outside of town. Also gates are funnels and usually places that people are forces to go through and where people are located for PvP.
Solution:
You need other options for new player content near the town as a alternative when there are murder hobos at graveyard. It wont stop killing but it since a single murderhobo cant be in two places at once it will limit killing.
Fabernum stables is on the opposite side of the town from the stables. Even tho its close to the red priest there is very little killing there. Mainly because everyone else is on the other side of town.
Just putting another graveyard or even a small scoundrel camp outside fabernum on stable side or behind would do a lot to help solve the noob killing. Noobs are no longer forced just to one location.
Carrot and stick approach -
With the old game play loop people complained that it was to rewarding to force people to go kill risars for reputation after they "killed" people. But that system worked better then the current one at protecting new players because players would still place a value next to each kill based off of the quality of PvP they would get. Noobs were left alone for the most part.
Just having reputation as something that can be reasonably obtained means that people can have reputation to spend on PvP. They will go back to being more choosy with the way they PvP as they now have something to lose. They spend too much on PvP they now will leave the hubs and towns in order to not have to lose more rep and will go far away to gain reputation.
The above gameplay loop does several things which is get players who PvP away from town lowering the number of people willing the PvP noobs. It also provides a enjoyable gameplay loop for the PvPer who will now have a better time in game as they PvE. The third thing is that it populates the world leading to more PvP outside of towns which will lure players away from town for better PvP.
The current rep gain system is a example of this but in a bad way because it gets people to go from one town to another and back again. People have started PvPing on their way back and forth between towns making now roads which were kinda void of players/PvP more active with killing. New players and vets are being put in the same place for rep gains which leads to bad experiences for the new players.
Solution:
Just give risar head rep exchange. Its planned by SV but they made the huge blunder of removing a working system for a half implemented one. Will lead to the aforementioned positives. More carrots should be added both for neg rep players and blue players. Such as more reasons to leave town if you are lower reputation just as red player content which will get the people who dont care about rep away from towns.
Then more reasons to not go neg rep as a "quest like task" that you have to do if you break the threshold into -1 rep. Adding a extra requirement based on time traveling somewhere other then a risar camp would mean players associate more work if they go neg rep. Work they could avoid if they manage there rep choosingly.
A more work approach would also to be to add special content for players with negative rep outside of towns. Things that would get a player to leave town to go out to complete this content. Make it time gated so that way after completing this content they will return to their normal play only to need to redo it eventually drawing them away from towns again.
BDO had some repeatable red player dailies that you got from the NPCs in the red desert area which was a red player area. It drew the players who wanted to be red like me, but wants rewarding enough to make us stay at that red town.
You will never get rid of red players. In BDO I would be greifed so hard by blue players who would kill steal and purposefully die to make you go red that I decided just to stay as a red player so they could not grief me anymore. I would offer duels and even let them finish their daily EXP boost but a lot of these people were self serving and would claim your spot. Crime systems never can understand context or be fair. Making players go red is a common griefer tactic and being able to fight those people is a big reason I play this game.