My 40th EUIV run: Luristan.
Yes, kind of a weird choice, but since I'm running out of ideas what to play until the 1.34 update gets released, I decided to go for Luristan, since it most likely won't get any kind of flavour or a mission tree anyways, so why not try it now?
Luristan starts in a dire situation, it starts as a vassal of Ajam, it's tribal, it hasn't embraced Feudalism and all of its provinces are mountainous, so not a chance to spawn any institution there. Luckily, Ajam at least shared its knowledge of Feudalism to me, while I looked for supporters for my independence. I tried the Ottomans and Mamluks, but I couldn't convince them. In a few years Qara Qoyunlu finally agreed and I declared my independence war. Since I had -3 stab now, I also took the opportunity to become Shia. The war went very smoothly, while their army besieged Tabriz, we took their fortresses, to trap their army there, it couldn't retreat anywhere, so we stack wiped it. In the peace treaty I took 2 of my cores from Ajam and gave some provinces to Qara Qoyunlu, as well. While they're my potential enemy in the future, I needed a strong ally, to protect me from stronger neighbours, who seek my land.
Next I had to wait for my truce to expire with Ajam, I didn't have any other routes to expand, because Mushasha was allied to Qara Qoyunlu. While I had made sure that Qara Qoyunlu can protect our flank against Ajam by its own, I attacked Mushasha together with my ally Mazandaran, so that Qara Qoyunlu doesn't get involved. I managed to win both wars, I showed strength to to Ajam, while taking as much as I could from Mushasha.
Now I had finally gained some good provinces that aren't mountainous and I could develop Renaissance. From then on, I no longer had to worry about surviving.
The next thing I had to do was break the alliance with Qara Qoyunlu to conquer Mesopotamia. I managed to get a new ally, Transoxania. They were mainly used as a deterrent and to help me subdue the Timurids and their ex-vassals.
After I had become one of the main great powers, I managed to secure an alliance with Austria and Lithuania, they were my main allies to help me to deal with the Ottomans. I knew that if I don't deal with them before they eat up the Mamluks, they are going after me next. I started my wars in 1650s and it took us around a century to destroy them as a threat.
My vassals: Mahran, Najd, Syria, Ardabil, Khorasan, Baluchistan.
My allies: Austria, Transoxiana. (Lithuania broke their alliance, because they desired my vassal lands in Tabriz and Mazandaran. Kind of absurd, since they didn't even border us)
For some reason, that one Native federation ended up having the modern USA-Canada border with British Newfoundland lol.