PoE nittor14 builds

hello fellow exiles, im currently onto my first red tier maps this league, im currently running a necro DD still using a tabula, my question would be whats the best version of the build atm, Blackflame for Chaos Ignite damage, or Polaric for more overall fire damage? Blackflame its very cheap atm and polaric its quite expensive for just 20% more fire damage, but i might be missing something I do have a 10ex budget atm, but i dont want to spend it on a +3% damage increase, to be honest i feel i do moderate damage on most bosses, i really wanted to be more tankier. (Trying to cap my chaos res