Attached is "provisory culmination" (just read that in a book...) of the Prop_Design_Geo Script for MoI.
There may still be errors.

The "tangent" points, and the two edge radius arcs, are created non-interactively.
Dealing with the leading edge and trailing edge, non-interactively, took about 100 lines of code.
This might be reduced a bit by calling a few functions..
Creating the points with interactive MoI takes perhaps 10 actions +/-.

Michaels help was invaluable.

Learned a great deal about MoI scripting, on this project.
:-))