They can change whatever they want but they better not change his lovey dovey personality.
Some are very loosely adapted. To be fair, the novel has a lot of characters and many plots going on. At this point I’m looking at it as a drama of its own.
I remember when YeLi went missing,he was ready to burn the world for her. He wanted the world to accompany her…
In the novel, she could, but not sure if Xiu Yao is as powerful in the drama as he is in the novel. Plus the Qilin was a product of her past as a modern day sniper.