PvP is why I came to play rift and the same goes for many others I play with, apart from constant re-balancing based off who shouts the loudest can anyone shine some light on where rift is going with respect to PvP content?

As far as I can tell aside from the ebb and flow that is "Balancing"? PvP Rifts = Port Scion with random pve mobs and usually less pvp. Escalation and other gimmicks that water down the value of favor and Valor.

How about some persistent battlegrounds that defients and guardians fight over zone wide ownership?

Zargo
Armada - Deepstrike