Well they were statistically the safest, anyway. There were a multiple more redshirts onboard that there were gold, and significantly more than blue. One gold uniform dying might represent 20 reds.
In Star Trek: The Motion Picture they were all pastels, shades of grey, and white. Wrath of Khan and Search for Spock were red, as you say. Yes, I would say that the red uniforms from the latter movies were the best of the originals. I think that they had the most nautical feel.
Well I prefer TOS films to any of the others and generally prefer the uniforms to the other incarnations of Star Trek. Mind you, I never had a problem with the supposed more "militaristic" elements of the TOS films either . . .