Troi was also barely Starfleet. Her training was primarily in psychology, therapy, diplomacy, etc. She didn't just enroll in Starfleet like everyone else and end up a ship's counselor; quite the opposite in fact. She went into psychology, and that took her to working for Starfleet.
In 'Disaster' O'brien has to remind Ro that Troi actually has rank, and Troi herself seems not used to dealing with people as an officer. She was practically a civilian, and thus she didn't have to dress the part as long as her Captain didn't object.
After Jellico forced her to wear a standard uniform, Troi started wanting to be more of an officer than a diplomat/counselor. She took the command test not long after, and showed more inititive and involvement as a result (grabbing the helm in Generations would be unheard of a few years back).
I always thought Troi was smoking hot, her aquamarine uniform being the absolute apotheosis of sexy until Jadzia showed up. I liked Crusher's lab coat, I think it was Starfleet's way to compensate for lack of pockets for someone like a physician who might need half a dozen gadgets on hand to do her job.
And I am shocked and appalled there is no war of pics of these ladies at their sexiest! For shame!