I'm playing a campaign with Tosa (Fall of the Samurai), very hard difficulty, and because of the geographical position of the clan, if I want to expand I have to protect several fronts, so I have a question. Usually my army consists of a single elite corps, pretty expensive to maintain. It is common for other clans, even allies, take advantage of my unprotected provinces, same with the navy. I have noticed that the other clans use a different tactic, they form large armies with a few elite units and filled with peasant units.

What do you do to deal with that situation?.