Another example. I always wondered why for the rectangle there is not the possibility to draw “around the curve”? This possibility exists for the circle, for the polygon, for the ellipse, by the square, but not for the rectangle.
These are small deficiencies, gaps in Rhino. I hope we do not have to rely on a script to do this! ehehehe 
This was present since 2008, command ptMeanCurves and more ptMeanGrid, ptMeanSurfaces (Paneling Tools)(Plugin)
Programing a new function, so that everything is not done,
Rhino SDK (all supported programming languages) must be complemented…
Rhino online and offline Help (with all languages) must be complemented…
Icons and Interface must be complemented…
and and
adding more spiral options to native rhino may be a can of worms… drawing or scripting a logarithmic spiral is easy compared to some of the other spiral types.
another type of spiral requested here before was the clothoid or cornu.
i can see what’s supposed to be happening with it but the mathematics involved are beyond my realm.
i guess my point is this- if only logarithmic spiral were added to rhino, it will be a little silly since it’s still pretty basic in spiral-land (the next step from continuous spirals)… if the discussion is whether or not to add more advanced spirals natively, i personally feel it would make more sense to offer some of the other more difficult spirals in a reworked _Spiral command as well…
which adds even more development time / resources… and a more difficult decision on whether or not it’s worth it for mcneel staff to take on.
I’d say it would be very worth it, particularly if the benefits were integrated into the Helix command.
Bump…
Interesting addition, Pascal!
I always wondered why there is the command “constant spiral” and not a “logarithmic spiral.” Equally, because you can draw a polygon around a curve, and not a rectangle … Small deficiencies that, finally, will be resolved.
THANK YOU