These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Big Lipped Alligator Moment: Several, even taking into account the show's general style. The usual reaction to a BLAM is the likely intention, too.
Ear Worm: The Brunnen-G's fight song, so much so that it was made into the opening credits track for the audience's sake.
Genius Bonus: The Higgs Boson apparently can't be measured without causing a planet to implode into a stranglet.
Hell Is That Noise: Throughout season 2, the Mantrid Drones' creepy, angry mechanical whining, and they swarm in the quintillions.
Hollywood Pudgy: A research assistant who is smitten with Kai in Season 4, the disciples of "Woz", others. Tended to meet bad ends of the innocent victim variety, whereas anybody with supermodel proportions meets a bad end due to bad choices.
Brother Trager falls in love with Stan in "Nook". It is completely one-sided on Trager's part, and Stan comes across as a tad homophobic in response. He does his best to let Trager down as gently as possible, however, and at one point genuinely considers making an exception for him.
I Am Not Shazam: You'd be amazed by how many people thought that Zev/Xev is named Lexx.
Mondegreen: The chorus singing the Brunnen-G fight song embellishes certain syllables in odd ways, it's in a made-up language, and no official lyrics have really been released for it, so dozens of written versions are around the internet. However, the last episode is entitled "Yo Way Yo," which is the first line, and the track on the Brigadoom soundtrack is entitled "Jerhume Brunnen-G," the last line. Since the translation is known (Fighters fight the Fight / For their home and their heart / We fighters will win or die / Forever we are Brunnen-G) the third line must be based on the first, so it's likely "Yo Way Ra(h)." The second line is still a mystery and up to the listener's ear to decide.
Moral Event Horizon: 790 comes close in Haley's Comet, but he finally crosses the line between unhealthy obsession and outright evil when he takes advantage of the Lexx's senility to trick it into blowing up the Earth, to prevent anyone on the planet from ever making eyes at Kai.
Stan does this when he decides to blow up the Water Planet in Season 3 all to save the life of one woman. Prince even proves this when it becomes the act that gets Stan eternally condemned to the Fire Planet.
So Cool Its Awesome: A bit subjective perhaps, but few who actually watched the show on a serious basis would deny that it was one of the great underrated and unnoticed Space Opera television series of all time. It is however, so into Fetish Fuel that some people have difficulties dealing with it.
Special Effect Failure: Most of the CG and blue screen effects in the first season are not convincing, and the same effects from the later seasons have not aged well (not to mention an extremely bad Chroma Key sequence when the crew are escaping from Mantrid's prison in the second season opener). As mentioned above, however, some see it as Narm Charm.
The interior of the Lexx was originally this trope, until Season 2, in which the show got a higher budget, resulting in a complete overhaul of the sets. This is even explained in-universe, as the Lexx was still growing during Season 1, but has fully matured by Season 2.
True Art Is Incomprehensible: Kai's living reincarnation in season four is an actor/performance artist whose own interpretation of Shakespeare's Henry V has to be seen to be believed, falling somewhere between preciously pretentious and "holy shit, did he really just do that?"
The Woobie: Zev/Xev. For starters, her parents sell her to the Wife Bank as an infant, resulting in her spending her life being raised "in a box" by a hologram instructing her on how to be a submissive but sexually aggressive wife. When she is released, she is purchased by the parents of a Spoiled Brat to be his wife, but after hearing his insults directed at her appearance, Zev lost it and punched him in the face. She was then arrested and put on trial for "failing her wifely duties" and sentenced to be transformed into a love slave, and we all know how that turned out. To top it all off, the only man she's ever loved is incapable of returning her affections, both physically and mentally.