I usually manually assign different font color,size and attribute for every appliance (router, switch,..,etc) I add to my project.
Every time I add new appliance I have to do this step right-click->Text Edit. if we have a separate default font for appliance as its form label style in Generale preferences->Topology view will be very helpful to set it once and use it anytime.
see the picture bellow:

All the fonts in blue currently set as the add note font or label font the blue fonts is the names of the devices and should be separated from the add note font.