Happy New year @laurent_delrieu new year, new release!!! 
I think your Polyline Region to Roof need a Medial Axis output too.
Seeing the result of your component, will a type of Medial Axis Offset approximation just for a single closed polyline be possible?
Again with idea to generate quadmesh.
Multiple polylines could be much more complex since the requirement is to mantian the number of control points.
MedialAxisOffset.gh (12.5 KB)
These papers for printing paths are related to offset it
ding2016.pdf (3.3 MB)
j.rcim.2015.01.003.pdf (5.0 MB)