You might be interested in my FoI Mage Slayer. I know it’s neither focusing on burn dmg or focusing on perma freeze, but with upcoming FoI buffs it could become rly strong: [1.1.4.2] [HC] The Weeb Hunter - fire FoI Mage Slayer [vids]
Yea this really nice for e.g. a callidor’s tempest burn build as you mentioned. Maybe I should adjust my build to have hardcapped Inferno 