Then, when I have labeled each vignette, I can move the vignettes into a pattern of ABCDE that I repeat as a way to weave the vignettes together like a braid, that has a familiar pattern, and then, when I compile them, they will be in that format ABCDE ABCDE ABCDE throughout the book.
Yup, you can do that with simple drag and drop. That sounds a lot like the approach I described above, then (whether or not they are sorted into folders is irrelevant, and in fact folders can even just be for your own use, not compiled at all—again that’s up to you). If each vignette type is colour-coded like that, it would be easy to make sure the order is right when you’re putting it all together in the Draft folder. Like I say, the compiler just takes your Draft folder from top to bottom. So if they are in ABCDE order in your Draft, that is how they will be when you compile.
But maybe each ABCDE needs a Chapter or Section Title? I am not sure.
I couldn’t say without knowing the source material. If chapters suit the narrative you are going for, then sure, use them. You might consult with your editor on that decision. I can say that personally I have enjoyed books that use either method.
I wouldn’t want it all melted together in the end, but for each vignette to be it’s own thing with space between each. I might want to insert a few blank pages between at times or here and there.
A space between text files is often the default. You can set that by going into the Separators compile option pane and checking the text/text separator.
For periodic page breaks you can use the “Page Break Before” checkbox in the Inspector (click the blue ‘i’ button on the far right of the main toolbar).