they're not one whole ship! it's three different timelines because both sun and i like Strong Women Who Can Kick Our Ass

otherwise, i suppose a main central theme with all these ships is emotional reconciliation. sun has his fair share of traumas that he has to unlearn and whichever timeline he's in, his partner helps in their own way both because of the bonds they share and the kindness they have.

and it goes both ways of/c bc sun's a giver and wants his beloved to be happy and recover past whatever baggage they may carry, whether it's the emotional hurt ch'en inflicted on hoshiguma by leaving the way she did in Ch 7-8 on top of the sole survivor guilt she has, reed's refusal to accept herself as anything more than just a traitorous shadow of a cruel king, or kal'tsit's inability to let her guard down and keep people at a distance