Depends what size figures I’m working with and what theme I am working to. 6mm I tend towards plain black, although I have been known to use a few stripes of white across them. 15mm I mostly go black undercoat then mix blue into the black and highlight a couple of times, although some of my sci-fi vehicles have high-tech green windows instead.
Never argue with an idiot. They'll only drag you down to their level and beat you with experience.