Especially with all of the fun but wacky builds that are popping up in RoS. Just having a full inventory full of damage absorption necklaces can be a duel breaker.
PvP needs its own PvP set for each class that can be balanced by the Blizzard design team. I know, I know. WoW clone... but it would be alot easier to build a system off of gear that uses *cough* pvp power to control the amount of damage pumped out and how much can be absorbed. Even before RoS D3 pvp favored either heavy damage or heavy toughness extremes. Now it really just favors heavy damage.
Here's a simple non-resource/dev time hogging suggestion:
PvP class sets that cost PvP tokens. Each PvP token costs bloodshards. You cannot enter the brawling arena without a full pvp set worn and cannot switch gear while in the brawling arena. Lets say after conversions each piece of PvP gear costs like 50k bloodshards. Grind that up in PvE to participate in PvP.
Once in PvP each kill awards bloodshards which can be used for gambling or purchasing PvP tokens for other classes if you want. The real reward comes from actually winning in the Brawling arena though. When you go into the arena you are locked in there until you win or lose based on most kills in a timed duration. Winning gets you a Token of Victory which can be used to enhance your PvP gear in some balanced way.
Simple way to control the stats for duels and provide a endgame content hopefully resulting in options like 1v1, FFA, and 2v2 teams. I would just like to enjoy some Diablo system PvP gameplay that I've been waiting for and will continue to wait for.