The section box in a 3D view has blue control arrows that can be extremely hard to see in the project. Every time I train people to use Revit, I have to walk to everyone's desk and show them exactly where the blue arrows are because they blend in far too much with the model. Even having used Revit consistently for 6+ years, I sometimes struggle seeing/locating the control arrows.
I believe that the solution would be quite simple since it is a very minimal user interface issue. Perhaps you can highlight the arrows with a semi-transparent white orb around the blue arrows. It is a minimal issue, but a daily annoyance.
Notice how hard the arrows are to see in this screenshot. This is a daily occurrence and I did not adjust the view intentionally to make them harder to see:
