There is obvious concern and exploitation of the ability to hop to a different server and be on the same hive, in the same place with the same gear (perhaps ready to kill).
There is a method you could try to stem PVP server hoping exploitation by introducing warning signals or messages that appear when a player logs in near you or if you are going to log in near other players.
This would provide knowledge of someone suddenly appearing in your building, for instance. It would also provide some comfort to players spawning in they wont get killed instantly.
The downside obviously is people will know when someone spawns in the area and engage appropriately.
A side effect would be less pvp in most servers at high value zones, more server used and more looted at those areas.
I think this would be an acceptable effect as the benefits outweigh the cons in my eyes.