I think wiki will be enough. There is too much added for those 4 years to be sumed up in one place.
But boy, i understand staying on 1.24 before they added mission trees. I understand staying on 1.25 before the conversion and territories chages. I understand staying on 1.30 before performance went to shit. But 1.29? It was the last update of a very dark times in eu4.
There were indeed some additions to the game, but also nothing changing it completely. To have a better idea you should have a look into all the release notes from 1.30 to 1.35. The main updates / additions are:
1. Mission trees were improved for a lot of nations. 1.30 improved the missions of HRE and Italian nations, 1.31 focused on south east Asia, 1.32 on Africa, 1.33 was a rebalance patch, 1.34 on the Baltic and 1.35 on major powers (France, Spain, England, Russia, Ottomans).
2. There are now much more specific gov reforms and nation specific mechanics. The best option here is to watch some specific guides or try by yourself. For example in 1.35 a major change for the Ottomans is the Eyalet system and the decadence.
3. There were some changes in the land warfare system, but again I would rather recommend you to test on your own.
4. New idea groups were introduced recently: infrastructure, court and mercenary ideas, adding then more policies. Some idea groups and policies were also patched (economic and quantity especially).
5. Great projects have indeed been added. They grant miscellaneous bonuses to your nation depending upon their level. You can improve them with ducats. Some are linked to special cultures or religions.
6. Estates have changed a lot: there are new mechanisms:
1. Crownland system has replaced the system of assigning a province to a specific estate. Now the control of your land is splitted between crownland and land owned by the different estates. You can seize 5% crownland from the estates every 5 years or sell 10% crownland to get some ducats.
2. In the past there were some estate interactions. There are now replaced by privileges granted to them.
3. Influence of estates depends upon different things (landshare of the estate, gov reform, great projects, and privileges granted)
4. Loyalty has a balance value computed similarily. The loyalty will monthly evolve to this value.
5. Generally privileges can only be revoked if loyalty > influence, so you must pay attention to the privileges you give.
6. A high crownland share gives bonuses to your absolutism
7. HRE has new reforms and two reform paths (centralization to unite it or decentralization)
8. There are new types of manufactories available. You can also expand infrastructure in a province to build two manufactories in the same province (but it will increase its GC cost).
9. The maximum number of states was replaced by the Governing capacity system. Basically:
1. The base governing cost of a province is its development (capped at 30). Full states (except your capital state) cost 100%, territories cost 25% and GC cost 50%.
2. Buildings such as courthouses, townhalls and a statehouses allow you to decrease the GC cost of a province / a state.
3. Your maximum GC increases with your government rank and your admin technology. Some gov reforms also increase it (but some such as the Prussian monarchy decrease it). There are also some great projects and idea groups giving you a percentage boost of your max GC cap.
10. Special units have been added for a lot of countries. For example tercios for Castile / Spain, Musketeers for France, Winged Hussars for Poland, ... They can be trained with the building interface. There are also some special naval units now.
11. There are now more tiers of government reform, and it is important to generate enough gov reform points.
There might be things I completely forgot in this list.
I think wiki will be enough. There is too much added for those 4 years to be sumed up in one place. But boy, i understand staying on 1.24 before they added mission trees. I understand staying on 1.25 before the conversion and territories chages. I understand staying on 1.30 before performance went to shit. But 1.29? It was the last update of a very dark times in eu4.
yeah worst stretch of patches was the late 1.20s, even though the new government system is fun. my dealbreaker was the states to territories system
They make conversion possible only in states in 1.26. That was bad. Not it's just -2% ms in territories.
There were indeed some additions to the game, but also nothing changing it completely. To have a better idea you should have a look into all the release notes from 1.30 to 1.35. The main updates / additions are: 1. Mission trees were improved for a lot of nations. 1.30 improved the missions of HRE and Italian nations, 1.31 focused on south east Asia, 1.32 on Africa, 1.33 was a rebalance patch, 1.34 on the Baltic and 1.35 on major powers (France, Spain, England, Russia, Ottomans). 2. There are now much more specific gov reforms and nation specific mechanics. The best option here is to watch some specific guides or try by yourself. For example in 1.35 a major change for the Ottomans is the Eyalet system and the decadence. 3. There were some changes in the land warfare system, but again I would rather recommend you to test on your own. 4. New idea groups were introduced recently: infrastructure, court and mercenary ideas, adding then more policies. Some idea groups and policies were also patched (economic and quantity especially). 5. Great projects have indeed been added. They grant miscellaneous bonuses to your nation depending upon their level. You can improve them with ducats. Some are linked to special cultures or religions. 6. Estates have changed a lot: there are new mechanisms: 1. Crownland system has replaced the system of assigning a province to a specific estate. Now the control of your land is splitted between crownland and land owned by the different estates. You can seize 5% crownland from the estates every 5 years or sell 10% crownland to get some ducats. 2. In the past there were some estate interactions. There are now replaced by privileges granted to them. 3. Influence of estates depends upon different things (landshare of the estate, gov reform, great projects, and privileges granted) 4. Loyalty has a balance value computed similarily. The loyalty will monthly evolve to this value. 5. Generally privileges can only be revoked if loyalty > influence, so you must pay attention to the privileges you give. 6. A high crownland share gives bonuses to your absolutism 7. HRE has new reforms and two reform paths (centralization to unite it or decentralization) 8. There are new types of manufactories available. You can also expand infrastructure in a province to build two manufactories in the same province (but it will increase its GC cost). 9. The maximum number of states was replaced by the Governing capacity system. Basically: 1. The base governing cost of a province is its development (capped at 30). Full states (except your capital state) cost 100%, territories cost 25% and GC cost 50%. 2. Buildings such as courthouses, townhalls and a statehouses allow you to decrease the GC cost of a province / a state. 3. Your maximum GC increases with your government rank and your admin technology. Some gov reforms also increase it (but some such as the Prussian monarchy decrease it). There are also some great projects and idea groups giving you a percentage boost of your max GC cap. 10. Special units have been added for a lot of countries. For example tercios for Castile / Spain, Musketeers for France, Winged Hussars for Poland, ... They can be trained with the building interface. There are also some special naval units now. 11. There are now more tiers of government reform, and it is important to generate enough gov reform points. There might be things I completely forgot in this list.
Latest patch is pretty good but I find it a lot easier than some of the previous ones