A proposal:
As we have at least three modules do measure distances
on the GRASS monitor, I would like to propose a merge
of d.measure, d.geodesic, and d.rhumbline.
The "new" module could be called d.measure, with
flags something like:
-r rhumbline following line at constant angle
-g geodesic following line along great circle
-m Output in meters instead of kilometers
-l Output in miles instead of kilometers
There should be also tests included if the user
is working in Lat/Long or not.
The merged code could go into 5.1 where most
display commands are present now.
Perhaps we find a volunteer to look into that.
Markus