I've reached a fairly interesting equilibrium with a character somewhere in the day 200s -- basically my army can beat just about any
one enemy army (and my main character is spending most of their time beating people to death unarmed to save on repair costs
) I've encountered... but the trick is outside the bandit clan type factions you don't actually fight those, especially not fast enough to finish before reinforcements come in.
So I've hit the point I can beat any similarly sized opponent I'm finding, sometimes even twice that number, but proper knock-down drag out late-game fights don't
have those kinds of fights. You get in a dustup with random character N and before the fight's over five of their friends have shown up and now you're up against 3-400 enemies, ha.
It's a pretty neat state to be in, actually. Piggybacking on proper faction fights is also quite nice, since you'll participate in fights with actually thousands of troops waiting in the wings. It's delightfully hectic.
Had one pretty amusing one last night, where I stepped in to help out a random civilian group that was getting attacked by the desert brotherhood or something, and part way through
I got reinforcements. Which was neat until we thoroughly trounced the bandits and it turns out the "help" was someone that hated me and a few of their friends, who immediately turned around and ganked me
... I reloaded to a day or two prior to that after seeing the options were "lose >50% of my gold by surrendering" or "lose even more gold, a quarter or so of my inventory, and rack up a huge number of injuries from losing the fight". Gotta' be careful where you're fighting if you know hostile folks are loitering around!