See, I wanted to say a fair bit, but Chris Bennett beat me to it. 
Jasminder Choudury and Miranda Kadohata are both excellent portrayals of professional officers who happen to be women. One has a fling with another officer after losing her entire world (common enough both IRL and in literature) and the other has nagging trouble balancing her career and family.
As for T'Ryssa Chen, this is a character that was long overdue. Spock created a stereotype that Lt. Chen butts up all the time, both in the books and in readers minds. She eats tropes for breakfast. Notice how Picard always had the "juvenile" Wesley or Data around to balance out his fatherly character. Chen has taken that role over well and added a good deal to it besides.
BTW I think a meeting between T'Ryss a Chen and Spock would be .... interesting.

Jasminder Choudury and Miranda Kadohata are both excellent portrayals of professional officers who happen to be women. One has a fling with another officer after losing her entire world (common enough both IRL and in literature) and the other has nagging trouble balancing her career and family.
As for T'Ryssa Chen, this is a character that was long overdue. Spock created a stereotype that Lt. Chen butts up all the time, both in the books and in readers minds. She eats tropes for breakfast. Notice how Picard always had the "juvenile" Wesley or Data around to balance out his fatherly character. Chen has taken that role over well and added a good deal to it besides.
BTW I think a meeting between T'Ryss a Chen and Spock would be .... interesting.

? How exactly does people being in relationships make something unintelligent? Did you ever watch the new Battlestar Galactica? That show had a ton of sex (and in the last two DVD releases nudity) and yet I believe most people consider it one of the smartest shows on TV in the last few years. Same goes for Lost, Rome ( I'm pretty sure Rome would be considered intelligent), and Dexter ( I consider it intelligent).