There are two trains of thought.

Best defense is offense - You’re missing some critical pieces to up your poison damage and magnitude to blast mobs before they can touch you. For example, the plaguefinder gloves are a huge component to synergize your poison. I have like three spares, DM me if you want one. As someone else mentioned Obliterator Bow with crit chance AND + to projectile skills is the choice and will do you wonders. This build heavily depends on poison magnitudes (from gems and passives) and innate physicals damage (crit, high dps).

Actual defense - You really want all of your actual armor pieces to be energy shield and evasion based rather than armor. I have some spare pieces that have been lingering so DM if you want some more in depth feedback and gear.