Or of course SubD by Thomthom for the organic form
About the "planar" pieces maybe take a look at the Slicer 6 by TIG
and the Lattice maker familly always by TIG!
@unknownuser said:
Converts edges and faces in a selected flat group into frames
PS About global structure maybe also take a look at the free TopMod !
(compatible to SketchUp by OBJ format)