It would be very interesting to know the basic strategies about:
But probably we have to wait for a manual 
At the moment, Dorico does not include any special casting-off behaviour for the ends of right-hand pages, e.g. to try to ensure that there is a rest suitable for a page turn at that point. We will probably add such things as options in future versions, but I don’t expect this to be in place before version 1.0.
You will, of course, be able to choose to end a system or a page anywhere you like – in the middle of a bar, if necessary, including in the middle of a beamed group, or even in the middle of a (nested) tuplet, if you really have to (though please do try to find another solution that won’t give your players the heebie-jeebies).
Dorico is capable of producing much tighter spacing without collisions than any of the other GUI-based scoring programs, because of the fundamentally smarter approach it takes to spacing. You can read about this in several of my development diary entries, including this one:
Of course there are plenty of parameters you can tweak to control default rhythmic (horizontal) spacing, and ideal vertical spacing, and you will be able to adjust both of these also on a case-by-case basis in Engrave mode as needed.
Thank you so much Daniel! 
Very interesting. 
I already read your link and I wonder if your smart algorithm has something to do with Knut’s bounding boxes glued together with stretchable and compressible glue, used in TeX and LaTeX…
Thanks again!
The actual spacing algorithm employed by Dorico is a straightforward rule to determine ideal rhythmic space used by traditional engravers, but the mechanics of how it determines when to deviate from that ideal space certainly has some conceptual similarity to the Knuth-Plass algorithms used in TeX. Spacing music is a much more difficult problem than spacing letters and words in lines and paragraphs, however, because it is multi-dimensional.
Thank you Daniel
Yes, music is very different and more difficult than text, and this was the reason behind the antique paleo-work of Tupin et. al with MusixTeX (which needed also a postprocessor, by the way). MusixTeX gave good results, but unfortunately the effort to introduce the music with a TeX-like language was too big, even with rudimentary tools…
Addendum: just to remember that Mathematical equations may be multidimensional like music and may take more than one page, as every PhD in Physics or Mathematics, using LaTeX, knows very well
Keep up the (very) good work