Hi,
I was interested in this as I am planning a dual purpose Sikh platoon with supports for N Africa and Malaya c.1942, and thought I would share some of the information I have uncovered (more to help other readers of this thread, as I am aware you are quite knowledgeable).
At the time of WW2, beards were as compulsory for all orthodox Sikh men as the turban, so all should have both. There is a move in the UK now for Sikhs to shave/wax, but back in 1942, removing any body hair was a no-no! It was, and still is, one of the five principal tenets of the Khalsa - the Sikh military society.
Even at this stage of the war, junior officers (company commander and below) would most likely be an Indian VCO (Viceroy Commissioned Officer), or less likely an Indian KCO (King's Commissioned Officer). A European KCO would be the least likely at platoon level.
Skin colour could vary, but tends to be in the mid-range for Indians.
Finally, when painting the straps, puttees and turbans, you said you used khaki/English uniform, but from the colour on screen, it looks more like khako drill. Can you please confirm which?
Thanks,
BvW