MOTM

Here is a simple(?) entry:

Pots:

Coarse Freq
(0)
Fine Freq
(0)
FM
(0)
Shape
(0)

Jacks:

(FM) (Shape)
(Sin Out) (Var Out)

The point of the Coarse Freq is to set a master range - much like a 
range switch you find on some LFOs. The Shape pot sets the shape of 
the Var waveform - from SAW to TRI (at middle setting) to rev SAW.
I don't know if it is technically possible to derive a SIN from a 
variable TRI/SAW waveform (hence I'm a customer, not a designer ;->)
With this layout you could use the 800/310 panel or add an LED and
use 
 the 850 panel.

Cheers,
Andy.