Right, you asked about the disc from my moon in that other thread ^.^ For my moon, i just had raised the “Source Angle” to 4, to get this nice disc.
And i think, some devs mentioned, that you should not add another atmospheric fog to your scene, if you have sky atmosphere. The Sky Atmosphere is the newer version of the atmospheric fog and replaces it, they basically do the same job. So adding both to your scene will cause false results.
Exponential height fog, that you can add to your scene, but i think, that caused some trouble right now, and will be addressed in 4.26. If i remember correct, it was mentioned here:
At min 15:00, they talk about sky atmosphere and exponential height fog, and at 15:32 they say, that the atmospheric fog is NOT compatible with the new sky atmosphere but the exponential height fog is, and it will be used for getting more control over the fog.
Edit: ok, they also adress how to set up exponential height fog with sky atmosphere shortly after taht, so keep watching.