If I understand what you’re getting at, this is often personal preference!
I tend to like a top-down approach with WM; working on small details when the big stuff is not finalized yet can be counter-productive as many times your fine-grained masks will depend on global operations, so getting them just-so and then changing the big picture can be frustrating.
So my workflow would be:
What do I want the terrain to look like very coarsely? Flesh it out with a Shapes device, or large scale noise if random
Start working on medium-scale (regional) features. This is where using multiple noise generators for different terrain areas, filters, erosion, etc comes in
Add in any specific features (level areas, roads, etc) once the above are mostly complete
Work on texturing and materials
And of course you can always go back and change stuff in step 1 late in the process; but proceeding in that fashion helps me get what I want most efficiently.