I've been looking at various forums with people proposing suggestions, but is there a consensus on what the collective noun is for "clouds"?
I don't know if there's some technical term used by meteorologists, but I think I'd instinctively say a "group" of clouds unless something more poetic was called for.
Remember it is OK to use plain, easily understood words when the fancy ones don't buy you anything. This reminds me of the pointless list of rarely used collective nouns for animals that some people think it's vitally important to their well-being to memorise.
I'd say it depends what kind of clouds they are (wispy, thick, black etc.) and what they are doing (moving slowly/quickly, thinning, thickening etc.). One possible collective term is a "scud" of clouds - meaning fast-moving, loose, vapoury clouds. I'm sure many more exist - I will edit if I think of them.
A collective noun for "clouds" would consist of one word or perhaps a compound word as "the cloud-cover" or "the cloud-covering" - don't know whether these words are in the dictionary. I don't think that there is a collective word for clouds. You could invent a word, perhaps "the clouding". - But, why are you interested in a collective word for clouds? In German we have collective words of the form Gebälk (all the beams under the roof), there are a lot of these word-formations, and you could find "Gewölk" (all the clouds), perhaps in poetry. But up to now I could do without "Gewölk". Do you see a need for a collective noun meaning "all the clouds"?