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.
Alas, Poor Scrappy: For some. Whether you liked her or not, it can't be disagreed that having Yugi give her a Break Them by Talking right before re-absorbing her by force (and when the poor kid is crying and begging Tenchi to help her!) was really cruel.
Growing the Beard: The second half of the series, which actually features Tenchi growing a spine and telling the girls to leave him the hell alone.
Recycled Script: The way the script ends, it could be called "An extended version of the Tsunami/Sasami" episode in the original series With Yugi instead of Sasami one day becoming a romantic rival as well
Relationship Sue: Subverted with Sakuya. She's the shadow of the Big Bad, and is just there to try to trap Tenchi. This means, she's a Relationship Sue and has to stay that way so the story works.
Alternatively, it could've shown how Tenchi would been as a normal student instead of an insanely powerful hero.
Also, the fact that this series is yet *another* AU storyline, rather than being a direct sequel to the previous Tenchi Universe series. It failed to capitalize on the previous TV series' blatant sequel hook ending, and the whole idea of the show (Tenchi deciding to move away from his crazy harem and go to school in the city; introducing a Muggle love interest outside of the Masaki harem...) feels like a sequel and deliberately plays off of the audiences' assumed familiarity with the characters and their relationships. Even the show itself seems to want to confuse the issue, what with its In Media Res opening episode, and not getting to the characters' origin stories until episode 7.