The Hitchhiker’s Guide to the Galaxy question

Hi everyone, I'm a Goodreads newbie so be gentle with me but I would like to add my own observations about Douglas Adams 'Hitchhikers'. Like many I read the books after hearing the radio series, liked it so much I bought the record (remember those?) of the sound track but no longer own the equipment to play it! I think Douglas Adams had the kind of author's mind that, like many of us who write, was a 'visual' writer's mind. I've asked others that write and some think and write in 'text' while others (myself included) write in 'scene', we see the story in our minds as a series of running scenes and we write what we see with dialogue added. Adams must have had a fantastic time being able to create the scenes in his head and then convert them into reality! By contrast, the other day I spoke to a writer of poetry and she told me there was no way she could write other than in 'text' and that she found it impossible to create her poetry through mentally visualising what she was trying to convey on paper.
Now I think that Douglas Adams, as brilliant as he was just began to run out of 'scenes' because writing in the same vein can be a considerable drain on the imagination! Not only that it can be boring for someone with a 'butterfly' mind, the sort that can suddenly latch on to an excellent idea but then finds it difficult to fill out to a book sized read.
After all that's said and done I could read and listen to 'Hitchhikers' at any time.

I don't think it got darker until So Long... which was surprisingly downbeat. I don't feel the quality declined at all. The tone changed, but that's the writer's prerogative.