Since Combustion is almost mandatory for demo; you can’t use dual pyre rings, I tried with dervish doesn’t even help. You can use crimson lotus aswell in Dervish but there is also not enough skill points to utilize lethal assault, nightblade wps’s and hardcap RF atleast for 24/26. And without utilizing WPS there is no need for nightblade side, you can play DW Fire Melee purifier, shieldbreaker, pyromancer, oppressor, defiler etc.
Though I definitely agree that we need atleast an MI chest/head/shoulder with cold>fire conversion. Using pyran is also so niche. My opinion is there should be a Fire Execution or Belgothian Shears modifier on somewhere.