Unstable idling

AD motor on VW 1302 Super Beetle has some tendency to stop after first idle mechanism being over for about 5 minutes, but later the functions are no problem OK?

Now the double diaphragm vacuum advancer is alive but retarder one is killed with BTDC 8 degree at #1 ignition timing, may be too much advanced?

Choke module finishes it's duty too quickly before warming up is not finished, in condition that the motor oil inside has much viscosity in cold temperature?

Too much carbon on ignition plug terminal caused by too rich fuel operation by choke phase?

I've some idea to overcome this inconvenience that the additional air circuitry with electric solenoid valve is applied between the vacuum nipples retarding and advancing ones for the purpose of idle speed up bypassing circuitry. The idle up valve by DENSO is utilized for air-conditioner operation, good idea, no?
Or another way to extend the working interval of choke valve, how about applying some adequate value resister in series in the electric circuitry. In another words, insertion of voltage divider in the circuitry to prolong the choke bimetal resistance spring effect. Of course an adequate value must be experimented and the suitable wattage also.

Because of too high idling, bypass screw was 120 degree tightened after the driving this morning.
By touching with finger on mechanical fuel pump and the metal pipe in fuel line proved that the percolation had not happened.

Solex 34PICT3 carburetor equipped Beetle let me know how precisely and perfectly the recent automobiles are electrically controlled on earth.