On a related note to what I've come to refer to as the Leytonverse:
One of the things that annoys me about Star Trek is that, as part of the tension, they're constantly setting up jerk aliens and antagonists often with the orb of stupidity in hand. I hate farce, and to paraphrase Buster Keaton the problem with it is that once you stop to talk and think it all falls apart, and that Star Trek narrative is a sort of farce. "You murdered so and so" and it turns out they didn't because obviously Picard or Riker or whoever didn't, but the aliens were stupid and it gets resolved, cue credits.
And on a related note, another thing that does annoy me is that you'll have the antagonists do something horrible or be jerks, and then have some Picard diplomacy treatment towards them and have them be let go or otherwise not properly dealt with. I do recall that happening quite a bit. It didn't happen as much in the TOS days, but the whole "We're better humans" 24th century thing really made it take off.
Something I like about the Mirror Universe and what I've seen of DS9 is there is a no nonsense mentality. It's like Liam Neeson in Taken; they aren't messing around. If you are a problem, you are getting vaporized; moving on. (And in the Mirror universe, everyone's the same type of jerk anyway, so it doesn't matter who does what to whom.)
That is really why I fell in love with Firefly as well, because one of the bad guys gave his whole "I'm gonna hunt you down" speech when he was captured and they were talking about letting him go, so Reynolds kicked him into the engine turbine to his death. In TNG had that same situation happened, Picard would have talked about duty and being better and all that sort of thing, and then there'd be an episode a season later where they came back and killed some people and endangered the crew. That's why it surprised me.
In the Leytonverse, I think it'd be a no nonsense universe. I think Leyton's Starfleet, regardless of if it's evil or not, would be no nonsense like that, and I think whatever rebellion there is would be no nonsense like that. The "easy to be a saint in paradise" rule applies, and the Leyton Starfleet would do it because they'd be more militaristic and it'd be the jerks who won.