Sorry if this has been posted already, I searched for it here, but couldn't find anything. I thought it would be up but maybe everyone is busy playing the game!
Yep that would be cool. The Mongol Invasion expansion for the original game added a mode called capture the maku (or something like it), where the objective of the battle was to take the maku of the other side. It was just a physical objective really, the enemy daimyo didn't stay in it.
Might make an intereting mode where both armies had to take each other's maku, and the general has to occupy it and not move. Reminds me of Uesugi Kenshin -v- Takeda Shingen at 4th Kawanakajima (though obviously Kenshin was out of his maku!)