Suggestions that i used from other players or made myself:
Uniting: Uniting will make countries well, form a union If 2 countries dont like eachother which is less likely than the alliance they will split
City Editor: Make cities for countries
Treaty mode: When a country takes the capital they will take a bit of lands other than the capital And this can be with size difference if the country won and they are a small country they will get 1 pixel which is less likely to 100 pixels which is more likely and the other way around. If they are half though the pixels will get randomized
Nuke Mode: Countrys can get nukes in 100 years to 500 years They can only have 5 nukes and if they are losing alot or getting close to the capital they will nuke a city or a capital which has a 80% chance of surrendering (only if its a city)
Some difficult landscape: Landscape like mountains Mountains should have depth size too if the mountains has 1 depth its a bit slow if its 5 depths its slow and 10 is very slow This will change alot
Exclave mode: a mode where countrys can have exclaves
Change Country Borders: Make so that you can change a countrys border
Make Countrys in Map Editor *with the country border editor too*: Preload countrys
Different Brushes: What i mean by different brushes is like making islands in a instant
Brushes Type: Islands (makes a random island) And add what ever you like
Force War/Alliances: Force a country to make war forever or allies forever
More Alliance Members:: When creating a alliance there should be Pacts where 3 or more countries can be allies