It is awesome to see you doing this Gigantic. This was one of my favorite books ever. I read it twice in two different translations. One was over 1600 pages long and the other was over 2400 pages long. The book had over 700 named characters and lasted over 100 years. The second translation by Robert Morse merged into the period after the Jin fell. Ostensibly the new faction that toppled the Jin traced it's lineage to the Han. You would have no shortage of characters to include. I do wonder what time period it will start in? Or perhaps will it have several starting times?
Yellow Turban Rebellion 184 AD
Rise of Dong Zhuo - 191 AD
Liu Bei at Xu province, Lu Bu in Puyang and campaigns against Cao Cao 194/5 AD
Just before Chi Bi the Wu Shu alliance - 208 AD
After Liu Bei takes Yi, 214/215 AD
After the formation of the Three Kingdoms 221 AD
You could probably include many more.