Thanks to Markus from Dorico German, I can finish a polished layout. Might be useful for others too:
He adviced me to always prefer layout options to manually move the staves around.
Best!
Yes: Dorico is fundamentally about working “from the general, to the particular”. Start with the Layout, Notation and Engraving Options; and set up your page templates as you want them.
Only then make manual adjustments as “exceptions” to what you’ve set up.
I have produced 100s of scores in Dorico, and most of them require NO manual adjustments, other than a couple of System Breaks here and there. I might do some “fine tuning” in Engrave mode, or a few Note Spacing changes, but it’s small potatoes.