The only thing I didn't like about the Nadia romance was that you get every single conversation with her right after Voss if you bring her with you while questing. So the whole thing seems incredibly rushed. Other than that, I liked it. I also liked Mako(out of all of the romance arcs, hers seems the most real but that's mostly because it developed over the course of the entire storyline like it should have. All romance companions should have been your first and second companions obtained so it has more time to develop). Ensign Temple was pretty meh, but Kaliyo was even worse. Both Risha and Akavi were awful(just like everything else about the smuggler storyline). Those are the only two I've played through all the way, but Vette is shaping out to be decent for my Lightside Sith Warrior.