For a while now when I've used Fume, I have struggled a lot with getting a good fire shader. The default just doesn't cut it. So like many people, I go nuts with gradients trying to get some rich detail out of the flame. After looking at various reference images, it dawned on me real fire looks like it has an "xray / fresnel" type intensity / opacity thing going on.
So for this experiment, I used my old gradient on the left, and on the right, I used the AFC with an "xray" curve to control opacity and a single color (keyless mode) to get the detail. These are color corrected with identical methods in After Effects.
The resolution of the sim is the same but I also took the opacity on the new one down to 0.01. I then just boosted the color to 25 to compensate. This lets you see through the fire, as opposed to it being one giant opaque mass.
This blog showing images of real flames inspired this idea...