When transferring to another instance of a zone, could we have zones you have to specifically scroll to and select that are PvP zones?

The PvP zones are divided into several level ranges (5-10,11-15,16-20,...) or whatever is most compatible.

OR

PvP can only occur when the attacker and defender are withing 3 levels of one another. Otherwise neither can be harmed by the other.

AND

Team members can't harm a fellow team mate while in the team.

In a PvP zone, all players are subject to attack without warning by other players.

Just a thought. Perhaps something for a test server?