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.
YMMV: Jyu Oh Sei
Asspull: Thor's chameleon ability is introduced late in the series, and only used once for some inexplicable and seemingly senseless reason, and only after it was brought to his attention by the plot. It makes sense in the manga though it's mostly symbolic.
Foe Yay: Thor/Zagi, and to some extent Thor/Third as well.
Ho Yay: Mostly between Thor and Third, and Thor and Zagi. Several scenes are just dripping with subtext.
Zagi especially can't keep his hands off of Thor, especially in the manga (where the Ho Yay is so obvious that Karim gets jealous of Thor). Third prefers the "getting into his face" method.
Third. He's so blatant about it that Thor calls him out on it at one point, but mostly he goes relatively undetected.
Zagi. He's a lot more subtle than Third, but he's playing half the planet as his cards. It's especially evident in Death Game with his coup de'etat of the Blanc Ring.
Starboarding: Tiz loves Thor who loves Karim who loves Zagi who is obsessed with Thor.
Tear Jerker: "It was me who killed Karim. ... So if you want to hate someone, hate me. Keep on hating me... so you won't ever forget me."
Toy Ship: Thanks to the shortened lifespan of humans (50 years even in the most medically advanced colonies), people tend to start relationships early. Just before Thor and Rai were sent to Chimera, the average age for marriage was about 14.
Unfortunate Implications: Despite women wielding power and being able to choose their own husbands, a woman who does not bear children is considered an oddity. Tiz even goes so far as to say that it is unnatural that she, at seventeen, has not had any children of her own.
This is justified given that they live in a half-civilized society, and have a short life-span. Thor even says in the end that the women of Chimaera are the saviors of humankind, or something to that effect (since they give birth to children who carry the genes of the new species, saving humankind after the old species becomes extinct).
Also, despite the fact that Chen and Karim have both proven themselves adept at fighting, they seem to prefer being weaker and more submissive to the masculine characters. Tiz is as well, but her fighting skills are more of an informed ability.
In the case of both Chen and Karim it's a result of them being infatuated with a certain man (Third and Zagi, respectively), especially Karim, who has a sort of a Masochism Tango with Zagi.
Even though the local society allows women the free pick of sexual partners, two principal female characters give up this privilege to fawn after men who are completely uninterested in them, and the other is in a Masochism Tango with a man who never admits that he cares about her.
This only really ends up being an unfortunate implication with the anime, as it cuts out so much information but the bare minimum so it makes it much harder to figure out what was going going on, for instance.
The homo sapiens that originated from Earth are dying out and the women are no longer able to bare children, and the children that are born are all basically test tube babies that have a very short lifespan. However, the females of species of humans on Kimera are the only ones in their entire star system that can still give birth. So they are the only ones passing on the genes of the next generation. So to the Vulcan system women, especially women who can give birth are naturally considered more valuable than men. This is a belief that the Hecate enforces onto the people, and why Tiz and Karim felt useless about not being able to have children, and why Chen chose to have Yuuki's children even though she was depressed.
the humans on Kimera are all instinct driven, not unlike animals, so the women from Kimera will naturally choose the strongest, most ambitious male to bare children with, and the since the higher ups want Kimerans to survive they created the system to weed out the weak for both genders, so that only the strongest survives and gets to pass on their genes.