I think there should be a /pvp and you can match make with someone and you can bet in a chest or something like u bring a diamond and the other guy brings a emerald you put the items in the chest and right click a green wool or sign to say you agree for the items the winner gets but if u click the red wool/sign then you don't like what there is to offer and u get sent back home with your items and in the chest your only allowed to take your items u placed in (that's the best I can explain this if u can explain it better the go ahead)
This would be in interesting type of PvP, because winner takes all, but sadly, as Larry said, PvP will NEVER be returning. Sorry, Danisonic