Rainbow Raider was a Flash rogue, created by Cary Bates and Don Heck in 1980. In case no one gets the name Roy G. Bivolo--a common way to remember the colours of the spectrum is the anagram Roy. G. Biv (red, orange, yellow, greeen. blue, indigo, violet). In the comics Roy wanted to be an artist, but he was colour blind. In THE FLASH TV episode, we see paintings at his hangout which looks like an art studio, so maybe Rainbow Raider is a frustrated artist.
The emotion thing was something the original Raider did with special spectacles. No relation to Green Lantern.
But it was the way that Caitlin explained the emotional spectrum as if it's real science that reminded me of the whole emotional spectrum in the Green Lantern comics. I find it kind of annoying to say all of that is science. I have no problem with things like AMETHYST, PRINCESS OF GEMWORLD because that doesn't pretend to be grounded in science. But I don't like it when the Green Lantern writers try to pass off this rainbow stuff as legitimate science fiction.