Elim Garak, because how can you not love a ~~patently duplicitous and yet still somehow generally benevolent smooth-talker who chews all the scenery and exudes the queerest energy~~ simple tailor?

It's a basic ass answer but Sisko. Star Trek has tried moral compromise a lot by now, but Sisko remains the only one where it really hit for me. Later Trek, where it's more common, just doesn't have the same level of professionalism or idealism for it to feel meaningful.

Janeway for me. She expresses anger in the right way and she sways her enemies with forgiveness. And she's a scientist.

Stamets, surprising absolutely no one.

He's the first gay main character, has a surprising amount of character development, has a great sense of humor and at first he reminds me way too much of me. Or at least how I used to be like. Then he grows into the person I'd like to be. Someone who cares about people and who tries to reach to others to help them when they need it.

Characters not perfect but I do love him. I will never not love him. I cannot tell you just how much seeing a gay character on screen was important to me. I grew up with Trek and there was so much diversity and inclusion for everyone but I was invisible. People pretended like I didn't exist in the real world so when the future didn't have me in it... It was disheartening. Still trusted in the promise of Star Trek and loved it but felt... Lonely.

When Stamets came on screen for the first time I absolutely hated him. Then slowly he started to grow on me. By the end of his second or third episode, I was already really soft on him but when they did the scene where Stamets is brushing his teeth with Culber and you become aware they're a couple?

I cried. A lot. For the first time I could see myself in Trek. For the first time there was real representation and love without shying away from it. Moreover, it wasn't dressed up. There was no forcing it. It didn't feel awkward or strange. It was perfect. They just did the scene like they would for anyone but it just happened that these people were gay. Stamets isn't the "gay character". He's a primary character who happens to be gay. I cannot tell you how much that means to me.

I will forever love Stamets for so so many reasons.

Garak

It's a tie between Mariner and Burnham.

Odo. Hmph.

The crystalline entity, because it's pretty.

Dukat. I don't like him a person, but he's a great character. No other Trek character has ever been written as richly or layeredly as he.

At first you assume he's your basic racist bent on hatred and power. Then you realize his obsession with Kira isn't just about destroying an enemy, but his secret love-hate for Bajoran women. We meet Ziyal whom he mostly loves, but is ashamed of. He goes mad, starts a cult, makes himself appear Bajoran and starts a relationship with Kai Winn (ostensibly with other motives, but I think he reveled in it), and ultimately dies for and in his mad faith.

DS9 is lower on my list when I rank the various series, but some of the characters, and defininitely Dukat, top the list of characters.

Spock.

The why should be obvious, but this video goes some way to explaining it.

Janeway is still my Captain.

But they have so many good characters in New world and lower decks... The new feeling and energy is so refreshing.

Chewingbacca. His laser sword was the best and he had nice eyes.

First, I love characters that are regularly puzzled by human beings / being human:
Spock
Data
Odo
The Doctor
Seven of Nine
Saru

Second, I love strong female characters:
Katherine Pulaski
Kira Nerys
Kathryn Janeway!!!
SNW Uhura
SNW Chapel

Third, I love queer characters:
Guinan
Garak
Jadzia Dax
Adira and Gray

I might have forgotten an awfull lot of equally amiable characters, which doesn't mean that I don't love them.