+ Fear of being ganked , it happened , i was one of the victim so i know the feeling .
+ No balance between classes .
+ Currently there is no reward in brawling .
However , we can work around , i say the battle of Bul-kathos in which he defends mount Arret against other nephalems is a good material for PVP , kinda like those capture the flags game , we can have easy difficulty which increase the HP of all player by 1000% , no one-shotting , and of course , hard difficulty which is your current set up , not only we must fight other players , we also have to fight ghostly nephalem NPCs which also drop item
Another idea is king of the hill style , players fight each other , kill the enemy to earn point and the team finish 100 point will win , but monsters will spawn in the arena , white , elite , bosses , goblin , you call it , killing them earn a larger point than killing player but you have to watch out for other players who will try to kill you and delay your team progress .