I also miss the fit to page zoom level which I very often used in Sibelius. So I could with one shortcut see the whole page on my screen. As much music as possible.
This would be very handy at least for me.
Thanks.
Maybe some day… 
You can customize that in Preferences-keyboard shortcuts. I’m not in front of Dorico right now, so I can’t describe the details. But I have such a shortcut myself.
View > Zoom > Whole Page already has the default shortcut Ctrl+Alt+0 (Windows) or Opt-Command-0 (Mac).
Thank you. I have overlooked that.
That’s great.