This is like wanting Hua Xiong and Yan Liang and Wen Chou to be added. For what purpose? These people don't have a story, just one appearance.
Like Guan Suo and Bao Sanniang?
Hmm Guan Suo has multiple appearances, depening on the source, but you're right about Bao Sanniang. Don't understand why they included her. She does have a story though, but not one that can be told through a game like this.
Like the THREE KINGDOMS? Please have a look here: http://thethreekingdoms.wikia.com/ -- a Wiki about the Three Kingdoms.
Historically Sha Moke never killed Gan Ning. Its only in fiction that he killed a rather ill Gan Ning while Ning was retreating from battle with an arrow. I'm sorry but if your biggest claim to fame is killing someone who is sick with an arrow then you dont deserve much recognition.