Its good to see some people are willing to play and to help in makeing such a great mod!
Dont forget that they make the 11th ROTK Game
and the 6th Dynasty Warriors Game, if you dont count the Extreme Legends, which are more or less extra games.
But i dont think the whole "Dynasty Warriors / Romace of the Three Kingdoms" thing like you said is done to death by now, its becomes even greater due to all the games, books and tv shows!
The most important thing would be all the different factions, like Dong Zhuo for example, who comes to great power but later loss all of it again, the world map would be in need of quite a flexible way. (strongly changing faction activity and the player would of course have a major effect on this, maybe he could even lead the Yellow Turbanes to glory.
Also leveling weapons, which should be possible, are good idea.
You would to have to choose a special weapon for that of course!
I included levelable Lu Bu Halberd weapon into my game, would need a new model of course. Just a test yet, but the weapon could also change model if it advance just like in the games.
There would be the need of new models and textures of course, because the current arent really fitting for most parts.