3. B’elanna Torres
Let’s be real. There’s why we say we like Star Trek, then there’s why we really like Star Trek. We say we like the utopian vision for humanity’s future, a future in which we’ve overcome evils like prejudice and avarice. That utopian vision is great, but what we really like about Star Trek is that everyone’s a big nerd. The heroes who save the galaxy on a weekly basis are all big nerds. Even those who aren’t traditional nerds, the lotharios, the daredevils, and the femme fatales are all big nerds too. Starfleet is an organization run by and for big nerds.
In much the same way that Tuvok expanded on how we’d traditionally seen Vulcans while remaining a Vulcan, B’elanna Torres expanded on how we’d traditionally seen big nerds while remaining a big nerd. She wasn’t a diligent A-type Starfleet cadet, she was a belligerent discontented rebel who flamed out of the academy and joined the Maquis. Yet when they found a robot floating in space, she was still the one staying up all night to fix it (don’t trust robots you find floating in space). She was a champion spouter of technobabble, whether the problem at hand was shooting Tom Paris off to warp 10, or cheese mold in the bio-neural gel packs
She ended up being what I think Chakotay was meant to be, the rough cynical avatar of the Maquis crew amongst the Pollyanna Starfleet officers.
Her half-Klingon, half-human heritage also gave her an inner conflict that was exceedingly well-handled, especially for a show that could be a little cack-handed with its character backstories. The Torres episodes are some of the best Star Trek episodes that Voyager gave us, some of which are unexpectedly moving, such as season 5’s Extreme Risk, and season 7’s Lineage, which was Voyager’s absolute best morality play episode.