Wonder if you have any idea how to make these. :) Hehe:
https://en.wikipedia.org/wiki/Cloud_iridescence
Beautiful!
The colour could be done with a power fractal (or a couple merged) plugged into the direct light modulator channel of a cloud layer. Then you'd just have to mask them into a convincing place.
Certainly achievable.
Hm, didn't think of that! :)
Maybe we are simply too afraid to actually use or try certain options out. I myself don't use some of the plugs provided. :D