Some issues in Control Room

Changing Monitors (A B C) in Control room need more than one second and disturb reproduction.
Changing mono to stereo switch (command: Select Next Downmix Presets) - the same!
Generaly, Cubase 10 is very slow - more slowest than Cubase 9.5 , almost unacceptable about that.

If it is possible - add to new update posibility to change LINK PANNERS option for more the one channel simultaneously (make changing for all selected track with only one check/click)

I’m new to mixing and I didn’t realise that “Follow Main Pan” or “Link Panners” was a “thing” until recently.
Did you find anyway of linking panners for more than one channel at a time?