1. Limiting zerging. It can be done in a few ways however speaking from my L2 experience the actual problem was having third parties getting involved in combat. There are few solutions to the problem.
a. Limiting access to the area by forcefully teleporting non-participants out of the zone whenever they enter it.
Pros: Does not allow 3rd party to join the conflict thus limiting the zerg.
Cons: Can lock out some players if the conflict area surrounds their hunting spot.
b. Higher death penalties (like losing equipment on death, increased damage taken, lower damage dealt to fighting factions) for getting involved as a 3rd party.
Pros:
High risk of losing progress might keep zergers at bay.
Players are not locked out from the hunting zones/activities.
Cons:
Accidental involvement in combat may cost players dearly.
Still allows for zerging
c. Instanced battlegrounds.
Pros:
Players involved are instanced so their actions does not affect 3rd parties, neither 3rd parties can get involved in the fight.
More complex mechanics can be introduced into the combat as they would be rendered in an instance instead of open world.
Cons:
Takes away human interaction from the event.
To keep bystanders entertained it'd require spectator mode which can be used to gain unfair advantage if implemented poorly.
2. Adding depth to the node wars to avoid fighting just for the sake of control. If there are certain goals which rewards both parties it incentivise more people to take part in it. And here I'm going to with the example I had in my mind for a long time for a project of my own it's going to be difficult to take it 1:1 into AoC but I hope you'll get the idea. So the combat is ongoing players complete the goals and are awarded currency. However if they die they drop some of it. The currency then can be used with special node Vendors to upgrade items as well as increase tier of lower tiered items. I believe it all happened to us when we got a piece of equipment which really fitted our play style but it simply lacked power in the end game and we had to turn to just another same +x to y piece only to be strong enough to compete. With this, gear progression would get some additional layer while at the same time we'd avoid scaling bs.
3. Expanding on L2's manor system. Once the faction is in control they could for example ban certain goods from being produced in an area. We're yet to see crafting system in detail, but lets say you control the node and you can chose which materials can be gathered or affect the yield of them in the area. So you'd mine more gold or quartz at the cost of iron this way you make the area more attractive to tinkerers or jewel crafters while making it more difficult for blacksmiths to get their resources. That way you can for example stack iron one week in your area and after switching to different materials you can make extra money by inflating the price of smithing services while you keep caravans taking different routes. Then this again creates opportunities for more PvP interaction outside of node wars like mugging the caravans which in turn again creates mercenary services more valuable in certain areas.
4. Mercenary system.
Unaffiliated players would be able to sign up as mercenaries and the party with less members registered for node war could be able to pay mercs via mercenary system to have them registered for combat with additional bonuses being paid to them upon completing certain objectives. Lets say the total cost of hiring a merc is 10k. Regardless of the outcome the merc is getting 30% of that, that is if they participated until the end. The remaining 70% is within the bonuses for objectives. If the main objective is completed and the merc side emerges victorious the merc gets 100%. Every side objective (as well as victory) provides mercs with mercenary currency which can be used at merc's vendor to grab some extra consumables, or pieces of equipment.
5. Instanced access to node dungeons.
The party controlling the node would have access to instanced versions of dungeons within their territory on a cooldown. Bosses would have reduced drop rates for items but they would be able to add modifiers to dungeons which in turn would provide different level of challenge and completing these challenges on a weekly basis would provide guilds access to additional rewards. This way we're giving PvP a meaning in PvE.
Most of the suggestions for inter-node war motivation have been Direct Advantages of going to war.
Can I suggest that it would be much healthier to have indirect objectives/consequences to going to war?
This means relying on other ways for nodes to interact with each other. Example: nodes placing tarriffs on each other - and a bad tarrif agreement is a great reason to go to war. Let the winner force their will on another node's relationship with them. OOFT juicy drama.
Inter-dependencies. Lots of interdependencies. juicy.
To me a war is a breakdown in relationship - so there must have been some sort of relationship (commercial or otherwise) to spawn a war. Otherwise the wars will feel artificial.
Comments
a. Limiting access to the area by forcefully teleporting non-participants out of the zone whenever they enter it.
Pros: Does not allow 3rd party to join the conflict thus limiting the zerg.
Cons: Can lock out some players if the conflict area surrounds their hunting spot.
b. Higher death penalties (like losing equipment on death, increased damage taken, lower damage dealt to fighting factions) for getting involved as a 3rd party.
Pros:
High risk of losing progress might keep zergers at bay.
Players are not locked out from the hunting zones/activities.
Cons:
Accidental involvement in combat may cost players dearly.
Still allows for zerging
c. Instanced battlegrounds.
Pros:
Players involved are instanced so their actions does not affect 3rd parties, neither 3rd parties can get involved in the fight.
More complex mechanics can be introduced into the combat as they would be rendered in an instance instead of open world.
Cons:
Takes away human interaction from the event.
To keep bystanders entertained it'd require spectator mode which can be used to gain unfair advantage if implemented poorly.
2. Adding depth to the node wars to avoid fighting just for the sake of control. If there are certain goals which rewards both parties it incentivise more people to take part in it. And here I'm going to with the example I had in my mind for a long time for a project of my own it's going to be difficult to take it 1:1 into AoC but I hope you'll get the idea. So the combat is ongoing players complete the goals and are awarded currency. However if they die they drop some of it. The currency then can be used with special node Vendors to upgrade items as well as increase tier of lower tiered items. I believe it all happened to us when we got a piece of equipment which really fitted our play style but it simply lacked power in the end game and we had to turn to just another same +x to y piece only to be strong enough to compete. With this, gear progression would get some additional layer while at the same time we'd avoid scaling bs.
3. Expanding on L2's manor system. Once the faction is in control they could for example ban certain goods from being produced in an area. We're yet to see crafting system in detail, but lets say you control the node and you can chose which materials can be gathered or affect the yield of them in the area. So you'd mine more gold or quartz at the cost of iron this way you make the area more attractive to tinkerers or jewel crafters while making it more difficult for blacksmiths to get their resources. That way you can for example stack iron one week in your area and after switching to different materials you can make extra money by inflating the price of smithing services while you keep caravans taking different routes. Then this again creates opportunities for more PvP interaction outside of node wars like mugging the caravans which in turn again creates mercenary services more valuable in certain areas.
4. Mercenary system.
Unaffiliated players would be able to sign up as mercenaries and the party with less members registered for node war could be able to pay mercs via mercenary system to have them registered for combat with additional bonuses being paid to them upon completing certain objectives. Lets say the total cost of hiring a merc is 10k. Regardless of the outcome the merc is getting 30% of that, that is if they participated until the end. The remaining 70% is within the bonuses for objectives. If the main objective is completed and the merc side emerges victorious the merc gets 100%. Every side objective (as well as victory) provides mercs with mercenary currency which can be used at merc's vendor to grab some extra consumables, or pieces of equipment.
5. Instanced access to node dungeons.
The party controlling the node would have access to instanced versions of dungeons within their territory on a cooldown. Bosses would have reduced drop rates for items but they would be able to add modifiers to dungeons which in turn would provide different level of challenge and completing these challenges on a weekly basis would provide guilds access to additional rewards. This way we're giving PvP a meaning in PvE.
I think this was called The Phantom Menace...