well thath`s quite good point it could be cross server, to balance the numbers on both sides, and the laggy thing if you have a full pvp planet with more than one front you will have your forces divided in order to take it so it couldnt be so laggy. If you have only point a and point b you will have both sides going to the same place at the same time. in the other scenario you will need to have pepole defening the other points or cities or bases, even with a lesser group you would be able to defend and retake other points on the planet less defended bases or cities no one could retain the 100% of the planet at all time its a lot of space .