It is too easy to get money.
I could make too much money with trade. When I buy meat for 8 and sell for 200 without travelling much it is far from realistic feel. It is especially trading with castles. When I buy it for 8 and sell for 70 in cities, it is exaggarated too, but gamewisely it might be OK. I wish if I would have such a business opportunity in real life.

Also it would be more logical if castle merchants would have fewer money than city merchants.
I had no exceptional trade skill in the party, only level 2 from a companion.
There were and are big salt mines in Poland. I miss them in the game.
Credit and deposit rates shouldn't change. At least not that much. It might be connected to renown in the game. If you want some change you should link it to the trade skill. More logical. Especially deposit rates must be stable.
Villages give too much money. They provide the same like a castle or city while in those there are huge costs from buildings and officers. So it is far better if I have a village.
Double barelled firearms shouldn't provide more damage and accuracy than an ordenary weapon. The two shots are enough reason to buy them.
Pistols should have less accuracy than a carbine.
Double barreled duch pistol has accuracy of 85 while double barreled duch carbine has only 80! Their accuracy and shot speed must be exchanged, too.
Firearms have too much reload speed. Compare rapid pistol with 66 speed to composite bow with 85.
I have seen a code in a mod which order troops in npc armies in level order in every 24 hours. This way the stronger troops appear at first like players do and battles will be harder.
It would be cool to have possibility to order my troops in settlements similarly like in my army.
When I defend a castle my troops gather at a single point and leave the towers and the other enty points almost unprotected. Only a few of the soldiers remain in place.
I see some soldiers fighting with firearms in melee even they have a sword!
Killing routing enemies should give only a few xp if any. I didn't checked it in the game but I suppose there is no difference.
Musketeers reload their weapon even in the middle of meelee. It is too easy to kill them.
Troops shot in heavy fog. I cannot see anything but my troops and the enemy are shooting.
The AI should never attack in a horde. They might attack quickly but they should do it in a line.
Soldiers should be aware to side attacks. Not just standing like sheeps in the butchery.
A better weapon balance would be better. I think there are for example 4 types of good pistols. But there is an obvious rank between them from good to less good. It would be better if one is a bit quicker, another one is more accurate, the third has more damage so the player need to choose which one he likes and not choosing automatically the best available.
I cannot control my men in siege as attacker. Only a few, 5-10 soldiers follow my orders. There is no logical reason who follows me, they are from different groups.
I cannot leave the walls of Pskov in siege thus climbing out.
Hmelnitsky's revenge: it would be better when the fight happens he gets some additional soldiers based on relative strength of the players and his party. It can be called a trap or something.
In my game when we fought he had 20 soldiers while I had more than 100 and allies. Strange revenge. But if he would get additional troops from the big nothing it would be some revenge or such.
It would like to skip tutorial when I start a new game.
It's not a big thing to make a different skin for salt and flour but it would make the trade a bit easier.