I'm a rookie at this game and I keep getting my butt kicked by the AI at this game:

1 - Legendary Geisha is unstoppable. It's like Terminator. She gets in, she kills my Daimyio, end of game. How do I stop her??

2 - After I wiped out 2 of my neighbours I reached the borders of another guy I never saw before. Looked ok for 1 or 2 turns until this guy threw at me 20-30 armies filled to the brim with soldiers (I mean his provinces closer to me were PACKED with armies made of 12 - 16 groups of 80). I didn't even know you could have so many armies.

Armies cost money to buy AND maintain, right? How does the AI do that? The only thing I am doing to my provinces is improve farmland. Is there anything else I can do to improve my revenue?

The manual that ships with the game is not that beefy...

Thanks for help

Yoda