In a real military, there is a WIDE VARIETY of different uniforms in use at any one time. It would be interesting to see this variety. The only time we saw anything remotely like this was in Generations.
Not entirely true. The variety of uniforms in
The Motion Picture approaches what you're talking about. Granted, the color palette was terrible, but you have to admit there was a little something for everyone. I especially liked the collared t-shirt variants. If they had kept the color scheme of the original show, it would have been perfect.
I always appreciated the idea of having a military structure in Star Trek, yet having a somewhat relaxed, utopian quality to it all. There's a command structure, but people can still relax and wear comfortable clothes, hang out in the arboretum, go to the recreation deck, kick back in bean bags, whatever (not that there were bean bags in Star Trek, but I would totally have replicated a few for my quarters, because bean bags are totally awesome).
The Wrath of Khan is obviously a great Star Trek film, but I feel like things got too far into a strict military structure than I would have wanted.
TNG got it just right--that was the original aim of
ST: Phase II, and that's precisely how I envision the "military" of the future being like.
TMP actually appeared to try and approach what
TNG perfected, and I liked that too.