Kate Mulgrew wanted to tackle one aspect of Kathryn Janeway that went under utilized

The concept for Star Trek: Voyager was always one that had two very unique elements to it. Firstly, there was the fact the ship was captained by a woman, a first for the television franchise. Kate Mulgrew was Kathryn Janeway, an even-tempered and proficient leader. Yet, while she had as much agency as anyone ever had as a Star Trek captain, she had the unique distinction of being the only captain in series history to be left out in the cold, some 70 years away from Earth in the Delta Quadrant.

This meant that Janeway would buck previous traditions set forth by past series like Star Trek in 1966, The Next Generation, and later Deep Space Nine. In all of those shows, not only were the leading characters men, but they all had romantic partners. Yet, due to Voyager's place in the galaxy at the time of the series, and with no eligible bachelors of similar ranks for her to cozy up to, Janeway was forced to be alone.

Romantically speaking. Not for a lack of trying, however, as Chakotay looked at her longingly more times than the series used the Voyager theme song to open an episode. They loved each other, and I refuse to believe otherwise.

Yet, due to his lower rank and the complications that would arise if she ever opened herself up to him emotionally, it never happened for those two. It was that loneliness that helped enshrine Janeway as a character; willing to venture forth and provide for her crew. Even if she was in hell.

When the series started, she had a fiance, a pet, and a life. Yet, by the time in the later seasons when communications were set up by the Federation, she came to find out that he assumed her dead and married someone else. Leaving her totally and ultimately alone.

It was a key element of her, though it was often buried. Something that Mulgrew wished she could have done more with. After all, how often do you get to see someone sacrifice everything for their crew like she had?

Speaking to the Fan Expo in Boston, Janeway spoke about how she wished the show had done more to highlight her struggles with being so alone at times, saying (via Cinemablend);

"They did one episode on the Captain's loneliness. It didn't seem to have much traction, but I thought they should've explored that throughout the run. I gave up my life as a young woman. I gave up the chance to have children. I had to break up with my fiancé, who quickly remarried. I had to say goodbye to my dog. As Captain, I could love, but only to a certain extent. And Janeway chose not to have a lover. I chose–Kate Mulgrew chose not to do that. So, the loneliness was harrowing. And I think it should've been a bit better revealed that just under the surface of her absolute devotion to this crew and her passion for science and exploration. But, you have to show the person, you know?"

The best episodes in Voyager's history are often the ones where Mulgrew is carrying the load emotionally. She's a tremendous actress and really shows bright in the more emotionally wrought scenarios. The episodes she dealt with romance, be it potential, fading, or otherwise, were also some of the better ones.

She was never depicted like Jean-Luc Picard or James T. Kirk, and so there was certainly potential to see more of a captain who would put her duty over desires. Especially when it came to Chakotay. Voyager avoided a will-they-won't-they scenario, and maybe that was for the best, but in the end, it just ended up hurting the depth of what Mulgrew could've shown off as an actress.