I have tried most in this game, before I mostly liked being the underdog and build a great empire. Now I am mostly looking for the most effective strategies and ways to expand.
I tend to stick to somewhat historical expansion, though not necessarily lining up with the time of the game. For example as France I'll try to recreate the Napoleonic empire, vassals and all.
I like to play some underdog against some Goliath and try to break it down. Also, not possible in the actual game, but some Estonian Empire in the Baltics could be a nice task.
Massive continental blob.
Must span at least most of one continent.
I've added in Estonia as a country in my game, because I got really annoyed that Estonian nationalists don't actually do anything.
+1
I like to start as a small country with western tech, focus on land and ignore naval units, trade and colonization, then I will look for the best opportunities to expand (conquest missions, holy war casus belli, excommunications, countries that are already getting owned by someone else) and I expand, in a somewhat conservative way, for instance before starting the next war I wait to have good stability, low WE, not extremely high revolt-risk.
I don't necessarily follow the historical developement of that country, even though sometimes that helps. I do a lot of diplomacy, trying to be friend of the most threatening countries.
When I expand I don't always annex, I like to vassalize too, when the target country has the same religious group, and after a while I annex them.
I don't like PUs because there's too much luck involved in inheriting, I prefer to have more control over what happens.
btw yea, continental blob ftw!
I cannot stand having armies with low morale so I always have military investment at max, to counter the cost I usually only have 60-70% of my forcelimits filled at a time. If someone declares on my my troops are battle ready THAT DAY and I can always build more.
I am like this because when I played for the first time as Castile I was following some guide about saving money and had low army maintenance and didn't react fast enough to a DoW and all my troops got destroyed due to low morale.