Huh. Without Liu Yu, Gongsun Zan would rise to power much quicker. Hell it be ironic if he let go of the "kill all tribes" mentality and recruits the tribes who want revenge for Liu Yu.
Barbarians they might be, they know to return kindness with kindness and cruelty with cruelty.
...not only that but we also got an in with Gongsun Zan thanks to family connections.
...holy shit. Liu He, Liu Yu son might come early into the battlefield to get revenge for his father. He is an palace attendant but he might be willing to put on armor, armed himself, get on a horse and go fight yellow turbans.
in OG timeline, he join Yuan Shao for revenge against Gongsun Zan for framing his father and decapitating him. There also Liu Yao who is brothers of Liu He and son of Liu Yu who became an warlord and Liu Ji who is son of Liu Yao who was favored by Sun Quao, one of the 3 emperors during the era of the 3 kingdoms ( Liu Shuo and Liu Shang were also Liu Ji brothers but they weren't important.)
Needless to say this changes things. For all we know, Liu Yu family might become close friends with Gongsun Zan....unless Gongsun Zan was behind Liu Yu death.