If you are looking for elite troops that might deserve special attention when they show up on the map board, black works nicely.
And if the color makes you uncomfortable, remember that black has traditionally been a sign of the bad guys...such as the black hat guy vs the white hat guy. Black counters are not glorifying the SS.
We must go to the experts for the proper period correct colours.
There was little change in fashion colors during the 1930s. In spring and summer, colour gravitated towards saturated pastels such as peach, rose pink, lilac, sunny yellow, sky blue, and sea green. Add to that year round colors of red, copen blue, emerald green, orange, and mustard.
Rose pink tunics anyone?