I would start by upgrading the other ring. Your Hellfire Ring is not worth using in my opinion. Use it when you want to grind out Paragon levels, but find a ring with crit chance. You will most likely lose some dex and some average dmg, but there are some very nice rings out there for your budget.
I would also suggest that you use Mantra of Conviction: Overawe instead of Mantra of Retribution. It's one of our best skills and using anything else is a dps downgrade.
Echoing Fury may increase your character sheet dps, but when you run after a feared mob, you aren't doing dps. Those on the top 10 on the dps rankings use Echoing Fury, but those of us that use weapons with no fear-proc will do more damage since the mobs are standing in our Sweeping Wind aoe.
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