i think the way they adressed fire build wasnt bad, maybe just remove some fire immunities in favor of magic immunes would balance it all out
plague runeword on act 5 does a good job for budget immunity breaking option for now i think
i agree with grumpykiten"s post just over me, those changes were rushed; most people that actually want the change seem to be casuals that only roll their only character and wish their own unique build was more efficient. There are other ways to adress that problem than by shuffling all the meta cards into a big mess
we really just need some more magic immunes instead of fire immunes, easy fix.