You can highlight the important connectors and
change the connector thickness
This option is
working at diagram and element level.
Selecting the Linck
Thickness menu from the diagram contextual menu will automaticly change
all links thickness.
Selecting the link
thickness menu from the element contextual menu, will only change the
link thickness of this selected element.
Click on the link, open the contextual menu and select one of the Link Tickness option: