I have to go with Baylan followed by Gideon

Surprised to see Qimir getting so many votes.

Not surprised, personally—and not just from recency bias or the fact that I threw him my vote too. Qimir is the showstopper, who above all the others completely rips away the heroes' sense of control over their story. His absolute massacre in "Night" is the point of no return. Jecki and Yord each go as far as to effectively beat him in the fight, and in any other story that would've been the end of it. Qimir kills them anyway.

Look, I'm fully on board with the understanding that Dedra is better written, Baylan takes all the cool factor, and Gideon is the best established in his series—but man, Qimir is the easiest to hate, and that's what really elevates him as a villain for me.

I really liked Gideon in the first two seasons of The Mandalorian. He was delightfully ambitious, ruthless, competent, cocky, and even humorous in a mean sort of way (the baby handcuffs he brought for Grogu...). I also enjoyed him in the meeting with other Imperial officials in the beginning of Season 3. However, the way his character was defeated was disappointing. The way he left the stage wasn't very impressive.

The Pyke boss wasn't noteable in any way.

I liked Reva for several reasons. Partly because of her ruthlessness and ambition in the first part of the show including her even going against the Grand Inquisitor. I also really liked her background, another result of Order 66, of the suffering and destruction brought on by the Sith. A child, lost in pain and trauma without anyone there to guide it, who seeks revenge on the evildoers only to end up in the same spot as them (or risk ending up there). A cycle of violence and hate: Hate begets hate begets hate.

So, I enjoyed her character all in all, her story (overall) seemed plausible to me, and I liked the idea of her returning to the light, but the writing could have been smoother in some parts.

Meero is one of the nastiest characters I've come across in SW. Nothing but hateful (although I do feel some sympathy for her for Cyril's creepy advances). Ruthless, efficient, ambitious. I liked her exchanges with her colleagues and her boss. She's probably the best written character in this poll (along with Qimir).

Baylan was an enjoyable antagonist, a capable fighter with convictions and interesting exchanges. But I'd have to (have) seen more of him and his goals to make a final conclusion of his character. Even though the actor has passed away, his character could still be explored in one way or another.

Mixed feelings on Qimir. Given that he slaughtered several characters I liked quite a bit, I can't say I liked him but he was terrifying and pretty competent. Great fighter, cunning, manipulative, good actor. I would have liked to see more of him and Osha (along with Darth Plagueis) and the remaining rest of the cast in another season. But oh well...

My personal ranking, most to least favorite, on top of my head...

1. Baylan Skoll

2. Moff Gideon, my vote

3. The Stranger/"Qimir"

4. Dedra Meero

5. Reva Sevander/Third Sister

6. The Pyke Boss

Baylan was arguably the best thing to come out of Ahsoka S1, though I do worry that my opinion may change should we see the character in S2, but we'll see. I almost put Gideon as my #1, as he is indeed the best established of these six. But while we've yet to see where Baylan goes, we did see Gideon's endgame in Mandalorian S3, which was a tad disappointing and could have been done better in my opinion. Still, I think the warlord has my vote.

I admit, I almost put Dedra in my top 3, because she was indeed more better written, but The Stranger is another case of being the best thing to come out of a disappointing series. And while one may consider The Acolyte easily one of the worst Star Wars shows, give credit where credit was due and say that Jedi massacre was a redeeming feature, akin to the Batman v Superman "Save Martha" warehouse fight of the Acolyte series, a good point in a terrible story. Though, just to have it said, I'd rather see a different series (or movie) than another season of Acolyte...that is unless the show can learn from its mistakes, but I doubt it. Then again, who knows, I may change my tune and give Dedra a promotion as #3, at least in my ranking above.

Reva...poor Reva. I'm sorry, but while the character did have some potential, I still see Third Sister as one of the weaker elements of what should have been the best Star Wars show. The Pyke Boss is no better, though unpopular opinion as it may be, I do consider Book of Boba Fett a guilty pleasure.

My compliments on the choices. It is kinda tough but I will only go with Gideon because of the way he was introduced: a war criminal who is cruel and ruthless and a former intelligence officer who knows everything about you.

What I like about Qimir is that he goes the Palpatine route of seducing you to the dark side very subtly.

What I like about Dedra Meero is that her story starts out making you want to cheer for her but later on you get creeped out by how sinister and evil she is. The weird dynamic she has with Karn only adds to the interest.

The Pyke boss and the inquisitor Reva were very one dimensional and are the least compelling.

Baylon was mysterious in his motivations which made him interesting.

Gideon just has them at Breaking Bad and untouchable villain feel, but not witless like Needa or vain like Tarkin

I vote Qimir, because he sad the most interesting thoughts among the rest.