My least favorite design however, would have to be the uniforms featured in Star Trek: The Motion Picture, as to me, they far too much resembled pyjamas, rather than uniforms of any sort. They were very... outlandish. Too stereotypically "futuristic," as in something from a B movie, no offence intended for those that believe it's a good design. Just my opinion.
No offense taken of course. But that kind of statement seems to come up a lot in these discussions, and I don't get it. It seems to imply either that we know what future uniforms would look like (as opposed to future pajamas), or that depictions of future uniforms should look like uniforms of today. But think of it this way: Would a US Navy sailor of the War of 1812, or even the Civil War, recognize the wash khakis and dungarees of World War II as naval uniforms? I don't think so.
If the criticism of the TMP uniforms is simply that they're ugly, I can understand that. I'm not crazy about their looks, especially the untucked shirt-tail look at the bottom of the blouses. But that's in the eye of the beholder. I like them the best because they are strong conceptually. There are different variants, some more formal, some for working. There are different protective and "occupational" additions. And surely short sleeves would be welcome sometimes. There are also some ties to TOS uniforms so the TMP outfits could reasonably be their descendants.
I like the TWOK uniforms the least. As I've said before, they are such a complete break with what was established before that it makes one think some kind of revolution must have taken place.