These are my probably horrible ideas on how to improve the game.
Players end: Needs less menu's and the ability to select multiple things in certain cases. Way too much clicking of buttons with no thinking behind them. Put everything at the top of the screen. Add in provincial unemployment. Make the tutorial less rubbish and have it explain things better, like unemployment being a thing.
Add in provincial unemployment.
Make it so stabilizing a province and changing ethnicities or cultures or religion s are separate things and that it will cause some instability and production penalties to the province but is better in the long term.
Make it so you can exile or kill ethnicities or religions, so you wont need to put effort into quelling them but this heavily damages your economy.
Lets say I want to as the Mongols make a deal with, Britain who lets say in this game hates Jews and my Mongolia hates Christianity. We make a trade. So I give him my Christians to save Britains Jews which come to Mongolia while the christians are shipped off to Britain.
Why are the numbers of troops so small? Have a setting to change how easy it is too amass and maintain a large amount pf troops. The ability to make provinces vassals or secret puppets.
Maybe have provinces work like this. Have it be so every province has a whitelist of provinces. The white list is of provences troops can get to in what ever amount of turns it takes. So if your in a marshland(Add this in.) province and you want to get to the forest province it takes 2 turns as marshland takes time to get through(Though it is very defensible as long as you have a fort or else there is no defense bonus compared to normal land). In a drop down bar. So you select a province which pops up a menu on the left side of the screen with all the information about the province and a new menu called the movement menu. Where you click on the amount of troops you want then on what province you want to travel too from that neighboring province which then says how many turns it will take. Usualy one turn. Make it so when you go to tell some troops to go to a province they arnt already "bordering" you can plan the route.
Attrition for armies. What about if you could train different types of troops made for certain types of land but are more expensive and get a harsher penalty in other types of land with attrition penalty.
Dont add in encircling.
Make it so countries wont randomly insult you at weird times even when they really liked you and you did nothing to make them not like you.
Make it so you can gift provinces and troops or slaves or population or products.
Make it so you can take loans and stuff from banks in specific countries and not just from the magic monopoly man.
Which if someone took alone from you and had interest to pay or debt. You could sell that interest and debt to other countries.
Remember when the king of the Byzantium sent back 900 men without eyes to a king who then had a heart attack. Why not get the occasional event after a war or battle or something. Have certain events in certain cultures religions and provinces.
I might be stupid but the way peace treaties work still confuses me. Why is it that I cant send an ultimatum to anyone to threaten a war unless they give me stuff. Why cant a promise certain land of an enemy to an ally before the war even starts as to get my ally in the war?
Where are the mountains? Why not make it so you can find mountain passes but only send so many troops at a time while at the same rime being able to build mountain pass forts which are super good and if you have a fort on each side of the pass and own it you can spend gold or population to widen the path so you fit as many soldiers a turn as you wish.
Add in a tech tree or something else to flesh tech out a little. Maybe add in an innovative stat if you the first or one of the first to reach a certain tech level or tech tree point. This innovation stat gives you more happiness economy development and diplomacy points. Make it so tech naturally goes up but to upgrade to higher tech or something to be more realistic. Add in different kind of tech levels. Make it so there are more ways of getting bonus movement and diplomacy points.
Towers are stupid get rid of them and make forts just do what towers do.
Make it so you can spy on other countries with spies and attempt to assassinate rulers which does stuff, I don't know.
Why is the made up mythical fairy tale landmass called Denmark in this historical game.
Add in illiteracy rates and languages. And make it so cultures, langauges or religions are grouped into certain catagories which influences how well countries and peoples can get along. Literacy rates effect development and economy. Are there any plans to add in a more interesting trade system? I havnt thought of a why trade could be more interesting my self.
Add a divisions system where you outfit what you want your troops to use. So you can have anti pole arm flamberge in front of your own polearm formation. So when you design divisions you design them in a box where you deside the amount of troops in it and there armament ifmthere at the front or the back.
I dont think I added this yet in my suggestions but add in taxes for specific provinces, tariffs and the ability to tax infidels and ethnicities. Also slavery and serfdom but I have no clue how these would work.
I think tech and political trees are the way to go.
So this is how I think the trade system should function.
Basic rules of trade:
All products have quality which costs moremto make without certain tech and other bonuses. This is important for booze which of course takes time to age and time is money. This effects every product. Now you could raise the price of products you make high quality or you could keep them the same price as why would someone buy from a competitor of the same price.
Provinces always buy the item in demand from whoever is selling it for the cheapest price. The price of the item is set buy the oroducer but cost is based on what it took to produce and transport. The only exception is if you foster nationalism and protectionism via political points.
Inside of provinces you will get a menu called consumers and producers. Which show producers which make things or refine them. like farms and steel mills which require another manufacturer to make things so they can refine them or produce more efficiently. Then you have consumers like military and livestock and stuff the player can build which I cant think of and along with population which consumes products made by the manufacturers.
The player builds producers and consumers in there own country. Which effects happiness growth economy and development and unemployment in provinces. And have losses and profits and if they go into debt for too long you need shrink or go bankrupt. But if its communist or fascist country the economy and development stat decreases efficiency decreases which increases scarcity or price. All of those factors lead to not being able to pay workers and too unhappiness and slavory aswell as revolts. Under the political tree you can research ways to supress your population which decreases revolts and all be happy communists.
Weapons: So basicly as tech advances you unlock new things like muskets and rifles and gattlingnguns and compressed air guns and cannons and artillery. Which you design divisions too use. So you can assign war animals and advanced weaponry or you can have shock trooper divisosn with 15mm thick breastplates and hemlets that ride elephants with a gattlingngun and charge the enemy.
Paint and dyes
Ores and Gems: This is pretty self explanatory. But gems are needed to create certain things as they are used for cutting.
Livestock: cows sheep alpacas llamas yadda yadda make differant wools which have differant uses and differant meats and differant cuts of meats and hides and glue and gelatin. Aswell as manure. Also eggs to make mayonnaise. These require food of course. Meat can be dried or turned into sausages. Certain animals require certain conditions to be raised which all provinces have a menu saying what can be raised in them. You also have bug farms for honey or what ever else they were used for historically. You can also get elephants to ride into battle. You can train tigers and leopards tomassign to,divisions aswell. Also you need to produce saddles and armour or what ever for animals too.
All provinces have a menu saying what crops can be grown in them and there production rate per orchids or fields planted in a province. Or pastures or factories built. This is effected by location and tech. Too much of factories or other polluters cuase the pollution stat on a province to increase which leads to bad stuff I dont know.
Certain plants need a certain tech level or location for them to be grown or grown profitably.
Types of wood: Cedar, pine, apple, cherry, oak yadda yadda Those trees then need to be logged, after being logged they are either turned into products, or milled to be turned into planks. Depending on the wood there is different uses and dfferant prices. Apple trees make apples sure but apple wood might be in high demand.
Ebony and ameranth wood is very expensive for example and can only be grown in west Africa.
Types of grain: Wheat, barley, outs, granola, canola, quinoa yadda yadda yadda Which can be turned into oil and food products for humans and animals. Certain grains must be pressed or milled.
Types of produce: Potatoes, tamatoes strawberries yadda yadda You can dry fruits and vegetables or make oils, booze, jams, jellies chips or even glop for sailers. There are canned beans and or tomato sauce.
Flowers: Can can be turned into seeds like sunflowers, candy and perfumes like roses.
Spice, herbs, weed, tobacco sugar tea and coffee things that are useless on there own: You have a few types of tea and coffee. Aswell as suger beets and suger cane. Spices like cinnimon and pepper of assorted colors or basil. You have mustard from mustard seeds. Grapes and hops for booze. Tequila pineapples to make honey water which can be refined into tequila. You have cotton too make thread and clothes.
Sealing fishing whaling, hunting: Blubber hide ivory anterlers, tusks horns.
EDIT: Maybe simplify things. Dont have induvidual animals and meats but instead red meat, poultry, gems, metals, hard wood, soft wood, exotic wood, ivory, spices, grain crops is one thing, refined grain, plant oils is one thing. This is just a simplified way of doing stuff so it doesnt take amillion years and wont hurt performance.