Honestly, an interesting take on the concept that had a bit of a peak in the late 80s/early 90s, was making the evil version of a good guy red, yellow, and black. I'm actually a huge fan of Captain Pollution and Negaduck's colour schemes.
I think we tend to associate red and yellow with warmth, and therefore with heroic characters. I mean look at how often those colours pop up on Autobots.
What I like about these inversions, though, is that it takes them and uses them with black, which turns it from a warm colour scheme to almost a toxic and corrupting scheme. In a world of "evil= colder and darker" I'd love to see this approach make a comeback here and there.
There's also the G2 Cybertronian colorscheme, (teal/green, silver/cream, mostly) which wasn't stereotypically evil-looking, but gave a menacing, skeletal vibe with the (largely) skull-based heads.
(Part of that was the uniformity/consistency, which IMO also helps combiner teams and subgroups-- like the G1 Predacons, who have a similar colorscheme to your examples.)
