Hey I tried pob a high budget tanky rf elementalist. Crit immune, 90 max res, capped chaos res with fourth vow, curse immune, edurance charges, 190 movement speed and still around 13 mil dps.
Not sure if there are better ways to scale defences fourth vow seemed like a decent option.
POBB: https://pobb.in/6LrknMNUu2ls