TNG Seasons 1-2: The science colour was darker and more greenish in this which imho looked better on both Gates McFadden and Marina Sirtis
IIRC, that was just because they wore those unis so much that, after being washed over and over, the blue became faded and greenish. (You'll notice that when somebody wears blue for the first time, like Picard in "Tapestry", it's very bright blue, because it's a brand new uni that hasn't been washed and faded.)
No, I'm literally talking about the uniforms Beverly and Troi wore in the Pilot which were darker/more greenish than the uniforms they wore later on (Season 3 and beyond) which had that terrible, bright 80s cyan. Picard's science uniform in Tapestry already was the post-Season 3 cyan.
However I can see your point when comparing Troi season 6 and 7. In Season 6 she looked terrible, in Season 7 she looked hot.
To be fair however, it might also be a lighting issue, the first two seasons seemed to have darker lighting than later on. Case in point the eternal debate whether the command shirts in TOS were meant to be gold/olive or avocado green
