Approximately what Mario suggest:
In 3D view I need to have (optionally) the coordinate axes.
After many rotations to see how it look from different positions I became disoriented. The coordinate axes could help me to know where I am.
It is already implemented in Modify opening... and Modify posture... preview BUT could be useful to be also on 3D view.
Option could be added as a checkbox under Modify 3D view...
or Preferences settings.