Tang12

While it is true, I prefer to start from this era as it was much more relatable for me personally

It is true that his army is no paper tiger, but his army lacks a cohesive command structure and only favored generals could hold the position of command, while Yan Liang and Wen Chou are very capable, the others he favored aren't so much and even lack the abilities, while capable generals such as Zhang He wasn't much favored and alongside Xu You betrayed Yuan Shao and supported Cao Cao. As for the imperial army, yes it has the combat power and experience by again without a good general, the army would go onto battle suicide because there's no strategy, and as for the Xiongnu and Wuhuan mercenaries and tribesmen, they are powerful at its own right but also lacked the teamwork and the tribesmen were subdued and doesn't care that we'll by Yuan Shao so any chance to escape or rebel will be taken by them But of course what you said is all right, Cao Cao's use of Tuntian and the Tiger and Lepiard Cavalry as the core helped him win against Yuan Shao, because in history and the novel, Cao Cao's army is smaller but there's the reason why it some said his army has the quality because they were well-taken care off, have capable generals, and advisors who are the best on the land and doesn't have an internal problem as Cao Cao would definitely scold them, unlike Yuan Shao wo prefer people who flatter and doesn't contradict him to obvious so as to not hurt his prestige