Balance Update:
Join Wars now require being neighbors in addition to other requirements, plus a higher opinion.

A revolt now gives 12 infantry 2 cavalry and 6 artillery (only if unlocked obviously) in addition to an extra 1 infantry per province, so now OPM revolts don't have such an incredibly weak army while larger revolts have swarms of infantry that end up bankrupting them. Now on average a revolt will have about 15,000, or 21,000 with artillery, but have more depending on large the nation is.
I might change this to 2 infantry per province to scale better.

Added a Peace treaty for the revolt tags of a revolt war, allowing them to instantly annex and gain a territorial core on occupied provinces. The idea is for a nation to split up into a few big tags, rather than always balkanize, and the successor states may break down further afterwards. In addition, it's supposed to be high-risk high-reward for a revolt tag, and it's supposed to be a "total war" type scenerio, where there is no truce but rather either side takes whatever they can get their hands on.

Balance of Power update!

AI Nations will now try to intervene in wars if a war upsets the balance of power via subsidies and condetarri.

Offensive wars grant a slight debuff for the war leader
Defensive wars grant a buff for the defender leader.

This means getting other nations to help is more valuable than ever and it's not so easy for a large nation to fight an offensive war against another larger war, while in vanilla EU4 France could for example invade spain and take more and more provinces (or vice versa) Without any pushback by other European powers or any consequence for the invader as long as they are winning.

Join Wars diplomatic action.
Requires (Nation joining the war, we will call nation A) to not be at war, to not be in a truce with the nation they are going to fight (Nation C) and have 100 opinion of the nation they are joining on the behalf of (Nation B) in addition to having an opinion that is negative of Nation C.
This means diplomacy matters more along with setting rivals and such.

Also opinion modifiers have been tweaked, "enemy of my enemy" has a higher max, the intended goal is to make alliances shift more frequently.

Misc. A minor buff for AI nations that seem to have issues for whatever reason (my guess is events + long troop movement. This could be considered a cheat but it's just to balance out the AI nations that always struggle, with the goal being to keep the dynamic in Europe relatively the same.
Nations that get it:

England: England seems to always fall into massive revolts and be splintered, which doesn't really make sense and i have no idea why.

Sweden: they seem to always have Finland revolt, and there is also an event with the Sami, both of which cause Sweden to struggle quite a bit compared to their real life dominance of the Baltic.

Brandenburg: They fail in vanilla EU4 lmao ever since Paradox changed the HRE with Emperor, plus made Bohemia stronger. They are already in a tough spot with Poland and getting the provinces to form Prussia.

Moscovy: I think the size of Russia and the time it takes to move troops causes them to always balkanize, even in vanilla EU4 they fail so often to Polish Commonwealth, hell even Lithuania by itself is a match for Moscovy.

France: Spain has issues too but generally if they Aragon they are fine, even without it they aren't pushovers. France seems to be 50/50 on whether they 1. collapse totally. 2. take over the region, get part of the British islands, and invade a weak Castile. The diplomatic changes should help prevent the latter a bit, so this modifier helps make sure the former doesn't happen frequently, so that West Europe is relatively as it should be.

Japan: i can't really do every Daimyo, way too many tags, but also it seems like they are fine, until they form Japan, then all of a sudden the unified Japan collapses for no reason, probably in part geography and so many nations that can get independence.

Ming: I don't really think i need to even explain this tbh.

The overall goal of these changes is to make diplomacy more realistic, and also to simulate Victoria's Crisis/diplomatic plays where nations will convene to discuss the future of the region.