In all google apps (earth, maps) and some others, double tap is used to zoom in a bit onto the tapped point. Quite convenient and also kind of standardized in mapping apps meanwhile. Would it make sense to make Locus behave equally?
Single tap could then be used to enabled/disable toolbars . Also more convenient since it reduces the number of taps required to hit a toolbar button.
Long tap is fine (address search). But even if the address search feature is turned off in settings, a long tap should still open a bubble for the tapped point (show the coordinates). That bubble needs to be clickable and offer the usual things you can do to a point (like waypoint adding, navigate, guide, etc).
+1 an all points
+1@2nd point
+1 all