Thinking of the Zhao clan
At this point, Zhao Kuangyin should have 2 sons (2 surviving of the original 4). Zhao Dezhou (prince Yanyi/the crown prince) should be about 11, making him around Ruby's age, which would be an interesting thing to make the young master deal with (they give us a lot of kids for them to get attached to) and Zhao Defang (prince chu) would be about 3 so I don't see him being introduced for a while - maybe just mentioned. The empress (Wang/Xiaoming)(edit for title mix up) will die within the next year or two (964) (edited for another oopsie) we follow the historical timeline but I don't know if that will be brought up.
We've had a taste of Big Zhao's love life with the introduction of Zhao Jingniang so it would be interesting if their whole situation is revisited with the added complexity of Big Zhao being married, having a haram, having a former dead wife (Lady He), and his current empress and mother of at least one of his children dying. Especially considering, based on the timeline, he likely met Zhao Jingniang while he was wandering in the 940s, in the build up to the creation of Later Zhou (the former dynasty), at which point he would have been freshly married to Lady He (an arrangement made by his father). We've had a lot of personal plot threads with him (and naturally most of his relevance will be as the emperor) but it would be interesting to see if they write anything for this (it could definitely be sad enough for them to play with).
There's also Zhao Guangmei (Zhao Tingmei/prince qi) - Zhao Kuangyin and Zhao Guangyi's younger half-brother. He wasn't a particularly influential prince (especially in Zhao Kuangyin's reign) so I don't expect he'll come up much in stories related to the court unless it's looking at the balance between bestowing positions based on status vs merit or criticising the overindulgent lifestyles those in power (he was notably reprimanded for arrogance and overindulgence, however many of these records are speculated to be biased and used to push him out of the court). He's about the young master's age (maybe a year younger) so if he's brought up, there's the potential to contrast him with the young master directly and, in turn, with his elder siblings.
With him, there's also the potential for discussions about birth status as Big Zhao and Er Zhao were both sons of the principle wife while he was the son of a concubine, making him of lower birth and potentially affecting the level of education he was allowed (there's very few records about it).
Overall, very nervous about Zhao Guangyi's storyline given the speculations about his hand in Zhao Kuangyin, Zhao Dezhao, Zhao Guangmei, and Zhao Defang's deaths however the way they approached Zhang Huaishen's gives me a little hope (since they took an angle about the Tang court that isn't particularly supported by scholars but works well for the story's purpose) that they might take some liberties or present alternate causes for their deaths that go against these speculations (I'm banking on the dream puppet parasite for Zhao Kuangyin in particular)
That being said, they've already taken some liberties with the Zhao brothers (Zhao Guangyi should be married by this point but he's not) so it's possible that the kids and last Zhao brother might not exist. I'd also be interested to see what they do with their mother (Empress Dowager Du), who should be dead by this point but apparently had them promise on her deathbed to pass the throne between them to avoid the issue of a child heir being made emperor (the source for this promise is considered dubious by a lot of historians and involves Zhao Pu, his future accusations of corruption, and is speculated to be used to put Zhao Guangyi on the throne after suspected foul play in Zhao Kuangyin's death)
