Here's a tip for HOT: Do NOT run berzerker/assassin. Run Soldier or Marauder gear for vitality/toughness. I can't overstate this, HOT becomes significantly more forgiving when you are running damage reduction on your gear. If you run glass cannon, prepare to be 2-shot. On my zerker Ele, HOT was a nightmare. Going through again on my Warrior running soldier stats, soloing around HOT was much, much easier and the difficulty was more even. These days I'm running Zerker on my warrior with Defense traited along with Dolyak signet to make up for lost defense, but I'm also just a better player now skill-wise and can avoid a lot more damage.