If you are running the build perfectly - like how to play it and such. Then all that is left is Paragon Levels - Augments on gear - and trying to get Primals. All those provide stat boosts. Also, having a good equip'd follower helps out a lot when running Solo. Yes, aiming to get those elites are a great plus as they give out progression orbs which speed up the clear time. Having him with a Unity ring (as well as yourself) and an invincibility item - means he won't die and you take 50% less damage - a must for surviving higher GR's.
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