I like the function editor a lot, but I find using it  for 'sculpting'  not very intuitive. The things I see you do in it, eonite, are very clever and inventive, but there should be a simpler way. For example for the lenticular clouds, you made the middle bit go up above the brim by changing the origin according to the position. That's brilliant, but really convoluted. I would have liked to have the overal shape separated from the density aspect. So I could define the shape mathematicaly, eg its a sphere, its a wave.  (and this shape will enclose 'most' of the density )
Also, I could have an object defining the shape and then change the material using the FE. At the moment I dont seem to be able to assign the same cloud material to an object as is defined using a cloud layer or even a meta cloud. I find this really frustrating. I can make a toranado shaped object in 5 minutes in a modelling program. but I cant assign to it a spectral cloud or meta cloud material.
(I tried to drop the meta cloud material onto an object but it wasnt the same after the copy)
Of course, maybe it is possible and I'm just doing it wrong...please enlighten me someone:)

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
http://artpearl.redbubble.com/