When events tracking are setted, Matomo displays an arrow on the dashboard to show that an event occured during a visit.
Instead of always get the arrow to indicate an event, it could be a good idea to have a set of expressive icons, so when setting an event, the Matomo user could chose the icon that suits the best to the concerned event.
Eg. A thumb up icon for a like, a comment icon, a call icon, an email icon, a share icon, ...
That sounds like a great idea for a plugin to me.