Maukka did it: [Reference] Nichia E17A/E21A (2000K - 6500K, R9050/R9080, color) CCT and tint shots - #49 by maukka
Maybe I was a bit optimistic about R9, but still, it could be nice.
But Luminus Xnova Cube 1800K is clearly better in terms of CRI (Luminus Xnova Cube 1800K 90CRI tested).
So, either E21A 2000K or Xnova Cube 1800K for the candle light fans (including me).