Rendering illustration lines

i’m working in an animation where a line has to be drawing defining the silhouette of a morphing volume.

I made the following animation with FinalToon from Cebas but it dosen’t give me all the control over the line that i need and the line seems a little crazy sometimes.

html://www.gaell.com/html/video/Coche_00.mov

Is there any other way to do this in 3d or postproduction?

I’m trying pencil+ plugin from psoft and seems to be much more control over the line and a more robust drawing of lines. Anyone know it?