For damage: 6-7× ED. Also sets could be Electrocution or Demonic or Living Force. Malestrom counts too.
For HP and reduction build most of the time: CV, Fauns Gift, Vampiric Touch , Plagued, etc. 6-7× HP. Some crystal 19% HP or balance 18%.
40% perseverance against bleed.
Then mythics: Cosmic orb mainly for the hit frequency and damage. Exposed (for pierce) or ruptured for bleed , (insert resource mythic here) and sanctuary as well as other options.
But the last thing to think about is the skill set and how you're gonna win. It's up to you but it's what works best for you and how well you survive as well as how many wins you can pull off.
It's hard to say PvP is unbalanced atm though.
I had difficulty adjusting to 2.5 PvP when I finally returned but I decided trial and error to try discordance orb and it just happened to work as I almost planned but half expected and I thought I was too old lol. What also helped is that I put the effort to learn how to reduce damage as well as efficient ways.
Also planning builds on paper/notes/spreadsheets/brain.