Here's an idea on developing open PvP with the existing game objects. It requires making the Eta Eridani Sector Block an open PvP zone. The instances linked to the various systems and bases will need to be redone as well, and there may be need of a few more starbases or base stations to increase strategic elements to the sector block.
The sector block will be open PvP, meaning that if you go in there, you're automatically flagged for PvP. In sector space, if players get close enough to each others 'bubble', then they will have an opportunity to engage in combat. All it takes is for one of the two to accept combat. An instance will be created and any players who can reach the engagement location in sector space within a finite amount of time, may join in. Once the time 'window' is closed, the battle begins. A marker of the engagement will be manifested on sector space, and when the battle is over, the marker will be replaced by the surviving player's ships.
There are two main strategic elements to the sector block, and they are bases and resources. Bases refers to both starbases and base stations, the former being larger, more fortified and well armed than the latter. Bases will be either deployed in a system or in deep space. Resources represent stockpiling of materials and logistical centers, and are situated in systems only. Entering a base marker would create an instance complete with a base in space that needs to be reached in order to board. Taking over key areas or a key area inside the base insures its capture. Resource markers will create instances of planets that must be reached in order to send an away team. A similar setup will be required to capture resources.
Normally, in sector space player ships can only see enemy ships if within a certain distance. However, when a faction owns all the bases in the sector block, that faction will be able to see all enemy ships on the sector map.
Resources work in a similar fashion, but affect the quality of loot drops in battles within the sector block. The more resources your faction owns, the greater the chance for you to get better loot from drops in battle.
When a faction controls all bases and resources, the war is won, and the map is flipped back.
With the judicious use of npc spawning, the possibility exists for making an exciting PvP environment that offers more than just the destruction of vessels.
If something like this works out well, there is the possibility for other open PvP neutral zones, such as Fed vs Romulan, and Klingon vs Romulan.