Summary:
-Death creates a combat limiting wound, with significant but not crippling advancement penalties. Wound can be partially healed by burial, and must be either waited out, quested away, or possibly healed with new medicins. Depending on abuse concerns, healing criteria can be altered to suit.
-New resource created from broken equipment on corpses and from resource fountains realms fight over. Scheduled weekend resource spawn events at the resource fountains give structured pvp opportunities, also include ability for realmless barbarians to take part. Ritual sacrifice to give a game mechanic for players wanting to destroy items for this resource, but with limits to prevent abusability.
-New magic to use the resource, or the resource gives XP and XP uses expanded. Possible magical expansions include new temporary realm abilities, temporary combat/non-combat buffs, gild crafting, wound healing.
For the longest time we've had the community arguing back and forth over the aspect of permadeath in Haven. It's both a unique quality, and a unique flaw that haven has in its genre of long term progress MMOs. Many people have advocated removing it, however I've never felt that they proposed a system to attempt to preserve any weight of combat and death in haven. At least I haven't read it in the 6+ years I've been visiting the Haven community on and off. Further I feel the weights of this problem reach deeply into the endgame stratification. All of the examples I'm aware of for long lasting MMOs that are in the sandbox genre feature PvP heavily as a form of emergent content. However, permadeath pvp makes haven pvp both appealing only to a notably small niche, and also an activity that can't be engaged in frequently due to the costs of preparation time. In haven even active fighters will get only a couple fights a week outside noob killing, while in other comparable sandboxes like EVE it's relatively easy to get into a couple fights per day. In games that haven't achieved lasting potential like Mortal Online or Darkfall, fights can be gotten hourly or more frequently.
Some people have proposed stat caps as a means to combat this issue, by capping the amount of work a character can intake, you cap both the time to rebuild and the time investment per character. However, attempting to stat cap haven low enough that it becomes reasonable for frequent combat would in my opinion at least require gutting much of what exists currently of haven's non-combat charm. Although a game like that might be viable, it's a shot in the dark and wouldn't really be haven in my mind.
This leaves me with three major points that need addressing in order to help haven's endgame:
1) Frequent pvp appears to be the only known successful formula for sandbox games.
2) In order to encourage pvp, some form of in game reward mechanic is usually required. Right now there is relatively little to fight over, especially since the sieging system is currently quite difficult. Things are either valuable enough to simply lock away behind a base shield, or are let to sit in the wild and checked with competition. However, weakening the sieging system is a dangerous issue due to the fact that "base permadeath" exists as well.
In order to address these issues, I'd like to propose the foundations for a combat endgame.
Rebirth System
The wounding system is reworked to replace the need for permadeath. When you die, you are either presented with the option of being reborn or logging off. Rebirth queues the screen shaking/screaming of being first spawned, and rebirths you at your hearthfire or an appropriate location if you lack one. Your corpse, and all of its belongings, remain at the scene of your death. At this point in the game, enough low magic has been introduced that rebirth no longer seems at odds with the gameworld hearthlings exist in.
A wound called "Mortal Reminder" appears. This lowers HHP to 1, and also reduces UA/Melee/Marksmanship by 99%. To keep the immersion and aesthetics, burial in all its forms continues to serve the function of repairing a % of the wound. The wound can be further repaired via specific rare medicines, preferably sourced from a non-bottable system that allows beginners to contribute to the war economy, by doing quests for your ancestor (a unique quest spirit named after your character that gives normal non-combat quests and heals portions of the wound as a reward), or very slowly over time. Since this wound only impacts combat attributes, there is no punishment to other non-combat aspects of gameplay outside potential equipment/mentory loss.
The primary importance of this system is that it keeps a high risk/reward in pvp that our current pvp playerbase enjoys, while reducing penalties for both newcomers to the system and non-combat types. To deal with issues of multiple corpses and abusability, each active corpse could only heal a proportional amount of the wound. If burial healed 50%, two corpses active, burying one corpse fully would heal 25% instead.
Edit: I realized after re-reading this makes it seem like mortal reminder would be the only wound. I love the existing wounding system, and would only want to see this added on top of it. I'm also not certain if this is "going too easy" on non-combat types, especially with regards to animals and how they should be a respected danger in the world. Some form of non-insignificant but also not crippling advancement penalty like -20% LP gain could be applied while mortal reminder exists.
Beacons of Wisdom
Right now we lack any gameplay oriented realm conflict. Realms have good reason to spread, but don't have any particular reason to conflict with each other. With the reworked death system, fighters could engage more freely in combat knowing that healing fully from a death would take a specific amount of work questing/time/medecin in order to be back at combat capability. To this order, I propose an additional rare structure exist in the world known as a "Beacon of Wisdom" or something appropriate. This would be an item that generates resources at a specific time on the weekend. However, this only happens if a realm claim is covering them, without a realm claim they lay inert. Realms would have the ability to shift the spawn time of the resources to aid in fitting their timezone, although it would be within a reasonable limit so that some realms couldn't simply set the contest time when almost no one is online.
The key to combat here is that the beacons are only lit for a limited but publicly known time, and take significant amount of time to finish harvesting. Hearthlings, either realmless barbarians or nefarious agents of opposing realms, will however have options to plunder the bounty for themselves if the host realm doesn't defend them appropriately. I'm going to be honest when I say that at this time I'm not 100% certain how this conflict should work. Some form of challenge beacon might be fairest, and cause the largest groups of players to fight by alerting the defending realm of the incoming raid. But at the same time it might make it too easy to defend as the strongest realm (the people who would arguably need the benefits the least).
However, it should always be that the defenders get greater rewards than the raiders if they manage to collect. This gives the cairn warfare a reason to take place during the week leading up to the weekly beacon rewards.
Blood Magic
At this point, it's important to discuss what exactly the rewards from beacons and killing are. Skulls in particular would need a rework, to avoid needles alt slaughtering and any potential LP shenanigans from them. I'd propose to deal with alt spam, only characters with 0 mortal reminder wounds give developed skulls (if they pass the other existing criteria). Depending on how balancing works, this might require that mortal reminder not actually heal over time but only via questing.
But beyond that, rewards do need to exist to encourage this combat. The two potential systems I can see are either XP rewards and its uses, or the creation of a new resource type entirely. To encourage gear degredation, character death could destroy items on the body and generate this reward item in an appropriate way. Mortal reminder wound checks would be done in order to prevent abusability. Alternatively, rather than having people simply take their farmer behind the shed, ritual sacrifice of crafters wearing good gear to generate that reward (for those who don't need combat stats while playing) could be incorporated as an explicit ingame act with appropriate sacrifice buildings/tools.
At this point it gets rather speculative as to what rewards could be offered. All currently existing magic in the game could be switched off XP and onto this new resource entirely. Alternatively new magical abilities, like temporary skill or combat buffs, could be introduced instead. Buffs like % bonus quality from resources collected are certainly a possibility given that exists as an ingame mechanic currently. Potentially guilding rocks/leaves could be forged via this mechanic with appropriate RNGness to ensure the resource is continually in demand. The potential for benefits can be spread into both crafting and combat elements.
Wrap up
I apologize this is long, everything that I feel is important ends up being lengthy. To anyone who made it this far, thanks for giving it a full read. I hope that this idea will spur increased amounts of combat, resource consumption to keep the crafters busy, and also aid in PvPers having resources to cycle back into the crafters to keep them interdependant in a way that keeps both sides of the equation happy. Mostly, I want to see Haven succeed, and the only way I see it moving forward is somehow reforming the negatives of permadeath before grand attempts at increasing the population.