"Fluid" Score layout

Hi, fellow Musescorers!

I have a score of 11 instruments that fit comfortably on an A4 page. Every once in a while voices get very high or very low or the notation simply requires much space above and/or below a staff. Those are the places, to which I fine-tune the page style settings, which means I have to reduce the staff distance (and also, since there is a piano, the grand staff distance. (The "Layout System Fill Threshold" is set to 1%.)
The consequence of this is, that, when there is little going on, Musescore squeezes the staves together quite tightly, so that there is a lot of white space to the bottom. (The screenshot show the problem and the settings.)

I know I can fix that manually using spacers - a great feature, by the way!!! - , it is just very time consuming and "breaks" as soon the layout moves measures from one page to another due to layout reasons.

So I wonder, if there is a feature that helps me improve the layout quicker? Something that I have overseen? Even a "drag staff" option would be most useful (It used to be SHIFT-[up/down arrow key] or mouse-drag?).

Thank you for any tips and tricks!
Robert

PS: There is a setting "staff distance" and "minimum staff distance". If the latter is larger then the former, nothing changes... Is that intended or a bug?