@antonis, RE high-contrast mode, I suppose if someone (@dos?) knows a terminal command to set it, then you could make a shortcut following a similar process to this, and place it on the home screen/app grid for easy access. (While we’re waiting for the automatic version to arrive.)
You might also want to create a shortcut to turn it off.
EDIT: The command is:
gsettings set org.gnome.desktop.interface gtk-theme 'HighContrast'
…and I made a tutorial to create shortcuts to use it.