It's my opinion that the realm divide mechanics needs to be modded radically. At the moment its a retardedly artificial way to make the game feel more "challenging" and it makes zero sense whatsoever. Clans should like or hate the player according to how the player treats them, not according to the fact that he's the shogun or not, or a candidate to overthrow the current shogun. There's already the territorial expansion mechanic that makes clan dislike excessively expansive daimiyos and the realm divide one is fairly redundant.
While I wouldn't remove the mechanic completely (probably it'd be harder to do too), i would drastically dampen it's effects.
At the moment realm divide starts at -50 and grows by 5 each turn, and it seems to have no negative limit, which is entirely out of line, since it completely ruins the diplomatic game during the endgame. While it's very possible to hold it at bay until victory, if one likes to continue past that, sooner or later he'll end hated, since ALL the positive effects have a upper limit.
The way I would mod it would be to make it start at -50, and make grow by 1 or 2 each turn (instead of 5), with a final limit of -100
That way it would still add "challenge" to the diplomatic game, but it wouldn't completely cripple it.
Any insight?