For me, I like the First contact/Late DS9 uniforms the best, with the movies II to VI uniforms pulling in a close second. I like them the best mainly because of the fact that they were all the same with only varying undershirt colors.
As for dress uniforms, I loved the First Contact dress uniforms. IMO they were the only dress uniforms that actually looked dressy. The dress uniforms from the late TNG era just didn't look like dress uniforms to me, because they retained the division branch color scheme... I don't think a red, blue, or mustard yellow anything would do well as some type of dressy uniform.
The early DS9/Voyager uniforms and the TNG seasons 3-7 uniforms tie for third place for me... Actually, the Voyager uniforms are probably slightly slightly slighty ahead...
Next for me would be the Star Trek XI uniforms, I actually liked them more than the original uniforms from TOS (I have a thing for layering I guess lol).
That would be followed by TOS uniforms, then the early TNG, with TMP uniforms coming in last.
I do also agree, the captains variations for TNG Picard, Sisko/FC Picard, and TOS Kirk were really interesting, and I liked them.