This is the best algorithm, and I would actually argue it should be applied to all obscured observations, regardless of their accuracy value.
Calculation for all observations would be:
- Disregarding accuracy value, calculate obscuring rectangle via the current method (0.2 x 0.2 degrees).
- Extend each side of the obscuring rectangle by the accuracy value (i.e. the radius of the accuracy circle). For observations with accuracy 0 m or undefined, the rectangle is the same as what is given by the current method. For all other observations, the square is enlarged, sometimes a little, sometimes a lot.
This obscures the pin equally for all observations, always includes the full extent of the accuracy circle, and displays as a rectangle rather than a circle to indicate obscuring has happened.