The Karma system doesn't work in my opinion because there's no point on allowing open world PVP but then trying to discourage it so much. It's like wanting the cake and eating it too: you want to have the low level players happy, which is important so people keep comming to the server, and also the PK/PVP players happy, which is also important for the sake of realism and because these players are usualy very active members of the community. But in the end, none of them is really happy with the system...
You see, it seems devs are trapped in a dilemma: we made a heavily oriented PVP game which is evidenced on the game design, action combat, etc. But we are not making enough money so we need to target the game somehow to a wider audience. So let's "ban" PVP, let's give a lot of importance to gear in detriment of skill, and in summary just import every mechanic from other traditional MMO so we can "steal" their audicence. But this is naive. Nobody is dropping WOW, FFXIV, or SWTOR for BD if it's not for the action oriented gameplay and PVP. Because BD will never catch its competitors in the traditional elements, and therefore will never catch their audience: the other games have years of develoment regarding those elements, and were already built around those mechanics, unlike BD. This situation must suck for them, I also thought that a PVP sandbox game like Alpha BD was going to be a massive success, and it wasn't. I understand this, but I don't think shifting to a traditional model is helping, because they are going to lose their initial audience, that HAD to play BD because there was no other similar game in the market. Uniqueness is always a key to success one way or another. BD is not unique anymore, well except for their character editor I guess.
But now to the issue. You shouldn't be punished for killing other players that are same level as you, or as I said, near your level, and if you are, it definetly shouldn't mess with experience or item drop rate. Moreover, this really breaks immersion, as being a "bandit" is something nobody would ever try if they know how karma works. Black Desert is supposedly a mature game, it is constantly advertised as having a real-scale world, but in reality it is one of the most peaceful and friendly worlds I've seen on an MMORPG. I went straight from 0 to 50 and I never ever felt in danger once. This is obvious, because computer enemies pose no threat, only players do, but they are so punished for "missbeheaving" that you don't need to worry about them at all.
Also, if you activate PVP mode, and someone with it not activated attacks you, you should be able to deffend yourself without penalty. I don't remember this happening (correct me if I'm wrong...). This mechanic is plainly stupid with all due respect...
About the lvl 30 limit for PVP, I find it pointless. First because there's no much difference between a level 10 player and a lvl 30 player: they are both new to the game, and they can not deffend theirselves at all from a high level player. So if a level 10 limit doesn't work, a level 30 limit works neither (really, there's a reason why PVP limit of asian servers is 50). Moreover, PVP level limits only generate frustration in my experiencie: people that want PVP will not be able to enjoy the game until they are level 30, in which moment they will be so anxious for PVP that they will either gank everything around or be constantly killed by the 30+ players (this is another peoblem of the game, levels/gear make a lot of difference in detriment of skill). If the game allowed PVP from the start, or from a very low level, everyone would be having their ups and downs with PVP from start, get used to it, and eventualy focus on other things, which would reduce ganking. This already happens in TERA, which targets a somehow similar audience as BD.
So in summary, leave the restriction at level 10: this protects players that are learning the basic controls, and at the same time allows players to get used to PVP as a regular thing in BD world. People is always "scared" that if you allow low lvl PVP then everyone will be ganked. But once a game is brave enough to do this, this supposed "ganking" never happens. Instead, everyone gets used to PVP and move on to other matters such as leveling. Leave karma for when you kill a player with a -5 level difference. Or hey at least let players CHOOSE if they want to PVP or not, either through a PVP server, or even through letting low level players enter on PVP mode from start and attack other players that also have PVP mode activated. You know, since nobody seems how to rework this karma system, just make this "little" additions to make PVP a lil more entertaining, maybe?
Sorry for the big post, and also for going slightly off topic, because this is for the bounty hunter system which seems cool, not for the broken karma system which is awful .