1. Por Rit is p'ek. He is smarter than his father because since young he was the most curious. He also works as diplomat/ trader with China.
2. N'ek came to the past because of Krisanakali Montra. Unlike Kade who stays at noble family, she stays with the servant gang at the market.
3. Similar to Kadesurang that come to the past to help making merit for real karakade, N'ek also have her own duty. Rompaeng didn't tell what it is.
4. Kade was so obsessed with foods, that's why we got series of menu in BPS. But N'ek in Prom Likit likes beauty and cleanliness. So she will introduce something like fashion design or comestic products.
5. She knows things that Kade does not know. Some history and stuff got updated or changed but Kade didn't know. Kade knows nothing about trade but new N'ek knows a lot about it.
6. Kade and Date will still play important roles in Prom Likit but we don't know if they choose new actors to replace them or just apply make up to make them more old.
7. N'ek might or might not have significant relation with Kade. We don't know. I guess the revelation will be similar to how Reungrit was revealed as Por Date in BPS!!!!
8. China and Ayuttaya trading.. Fujian, Guangdong etc..should be mentioned. We might see N'ek helping P'ek in this aspect.
9. Mae Malee and her 2 sons might have important roles in part 2. Malee refused to be wife of Prajao Seur so she was treated badly but in next reign, her life got better. Prajao Taisak got her to look after money and gold at the royal palace. Her sons have important roles at royal palace too and are favored by the new king.
10. Mae Prang (the youngest kid) might have a significant role too.
11. Rompaeng said the new N'ek will lead us to see more of the servant lives and she ensures it will bring laughter.
All in all, BPS cast that will be in Prom Likit should be:
Kade and Date, Mae Malee and both her sons, all of Kade/Date children, Janward's daughter (I think she might have some appearance in part 2 coz all the kids in BPS are close friends), Khun Ying Jumpa (hope her character is still alive
), all the servants at Kade/Date house, Got (might play as Prajao Seur and also Prajao Taisak which is Prajao Seur's son).
Regarding Janward and Reung, it's complicated. Coz in BPS novel version, Janward got married to Laung Siyuth. Khun Reung treated Por Rueng (Kade's son) as his own son since both have same name. Rueng Lek and Rueng Yai..that's what they address these two characters. The script writer changed this because Luang Siyuth is a real historical figure and his family descendent is still alive. Hence, we got Janward with Rueng as couples coz both are not real figures. I'm afraid we might not see them in Prom Likit.