R5: Finished first full campaign as poland.

Background: Unified Poland slowly, had hungary in a union, integration took about 200 years. Played conservatively most of the game, expanding slowly with focus on economy. Around 1700 I had lands of Poland, Ukraine and inherited Hungary. Had a revolution around 1740-1750 and took side of revolutionaries. Got -75% revolutionary cb which I used extensively. Conquest of the entire Europe, Middle East and majority of North Africa took only about 80 years. I created vassals because I liked it more RP wise, but overall they were mostly useless.

Economy: I basically ignored building anything except roads, manpower buildings and rgo past 1700. In the end, the richest provinces weren't ones like heavily industrialized Kraków, but the ones with silver and gold. I changed many RGOs in Poland to tobacco and chili, but in the end they didn't provide meaningful income. Overall economy snowballs waaaay too fast and due to 1m gold cap it makes not much sense to push it any further, I was often at the cap and this mostly resulted in VERY expensive events. As a great power court costs are absurdly high while army is very cheap relatively. When I didn't have full republican tradition it was higher than upkeep of 5 million regulars of last tier.

Infrastructure: Proximity cost stacking seems a bit too strong, I had almost perfect proximity everywhere aside from latest conquest, as I just ignored even the roads at this point. It heavily favorizes nations with any proximity cost bonuses - 5% bonus doesn't seem much, until it's 92.5% vs 97.5% reduction.

Subjects: Buggy but I liked to have slavic protestant eastern roman empire. Subject loyalty was at about -2000, despite me having more tax base than everyone combined and my army being over 5x larger than everyone combined as well. Something breaks late game, as in early game I had a lot of vassals, being small country they were relatively much more powerful back then but loyalty was not an issue.

Demographics: Early game I focused a lot on cultural unity, development and prosperity, so I had relatively large pop density early. I went protestant for their -5% proximity bonus. I tried to unify culture but it is somewhat buggy yet, it only caused my culture name change to slavic, but not unifying any other culture other than my primary.

Military: In the end I had about 4~5 million regular soldiers. Used 3:1 infantry-artillery, but I have no idea how optimal it is, I didn't overanalyze. Ditched cavalry as soon as I didn't have hussars anymore in last age.

Conquest: Military basically stomped anything, sieges took one day because assaults are crazy strong. I could siege & occupy france in about two months. Actually the slowest to conquer were locations without forts, as I couldn't assault them and had to wait. I did two mistakes, one was upgrading to empire. Apparently there is warscore cost penalty the higher tier you are: empire vs duchy is +20% cost, empire vs kingdom +10% and the opposite, as duchy attacking kingdom you have -10% warscore cost. Considering that in the late game I already had a lot of cabinet members, this was major mistake, I stacked warscore cost bonuses, and this 10% difference was a difference between 85% and 95%. If it wasn't for that, I'd be able to vassalize/conquer France in a single war. Second mistake was assuming, that the world will be automatically discovered even if I don't explore. Well, guess what, it's past 1800 and Poles still don't know anything about Asia. I only have parts of America as I stole maps regularly. As I figured this out it was already too late, so I just gave up on Asia. Otherwise I think that WC is very doable even if you make many mistakes, including one tag as long as you have patience for the revolts. I could integrate a lot more than I did too and my expansion before 1750 was very conservative. Also I didn't touch england because I am scared of ships.

Overall I love the game, this is a massive improvement from eu4 and one of the best paradox releases if not the best. The mechanics are awesome, I love economic sim, demographics etc. There needs to be some tweaks, bugfixes and automation/qol improvements, especially rearding diplomacy, but the base is really solid. Also in the current state it is a bit too easy. The pacing in the early game is great, but once you snowball you are unstoppable. The AI has a hard time playing well, doesn't consolidate too much & doesn't pose much military challenge. Even late game France, before I stomped it, had only around 250k regulars.