There is absolutely a power system, it just isn't mythical. A slave kid has to climb the rank from lone soldier to someone who can lead an army of 100s of thousands.
Imagine the Naruto world with all of those villages at constant war for hundreds of years. Rock, fire, leaf, stone, plus the minor ones like the rain. They were at 100, now there's only 7 left as they've crushed the others. Various states have different relationships with each other - alliances, betrayals etc. There are 'little finger' (GOT) characters who weasel up, create wars and try to rise in their political lives etc. Main character's state wants to unify it all.
Don't focus on the fact that it is 'china'. It could be any made up, fictional name you want. It has characters that would be considered gennin, chuunin, jounin elite joinin, kage etc. Each state would have their own equivalent of the Yonkou, if you like (Great Generals).
Main characters are from Qin.
The duels are quite spectacular. It's a very character-driven series where Generals are larger than life. Great Generals, even more so.
