Randomized World Settings: Part 2
This is going to be all about setting up religions. This is also pretty subjective as I do have a fair bit of experience in the game, but have not played every combination and only remember a portion that I have played.
In general terms, I like to split each religious group and have a wide range of options. So for Christianity, there are 14 separate religions. There are 6 different Nature options, so I lean towards having each of Nature options represented at least twice and then having a couple being represented by 3 different religions.
Cosmopolitan - Usually with religions with the largest footprint. Keeps them from overrunning everyone else.
Unyielding - Usually the Religions with the smallest footprint. Keeps them from getting overrun by everyone else.
Peaceful - Can be a little overpowered when playing depending on underlying tenants and doctrines. Low revolt risk and large demesnes can go a long way when building tall.
Warmongering - Generally on frontier areas with hostile religions. Example Christian vs Islam.
Dogmatic - I generally use this on mid tier religions as far as size.
Proselytizing - I use this on mid tier religions. Can be pretty fun with the right set of Doctrines and getting rulers to flip religion.
Doctrines are more of a mixed bag. Some are really good and some are kind of awful. I still try to mix it up as much as possible.
Agnatic or Enatic Clans - Both pretty good since you get Open Succession right from the start. Obviously, there is a lot of roleplay with either and being able to choose your heir and then they get everything with no real opinion penalty is a bit busted. Enatic is a bit weaker since it doesn't work with concubines and the father still has to legitimize children along with marriage defaulting to the males dynasty. I usually try to have one of the religions represented by each of these in each religious group.
Equality - I try to fit one of these into the larger religions groups. What makes it strong from the beginning is having twice as large a pool of candidates to choose from as far as advisors and commanders right from the start. You can attain equality, but it does take a fair bit of time.
Divine Marriage - I don't find it particularly useful, but there are a lot of role play aspects. I mean it wouldn't be CK2 if you couldn't marry your sister, niece, aunt.
Meritocracy - Can be good. However, with Agnatic or Enatic Clans, it becomes a bit pointless.
Stability - It's okay. I tend to use it in religions with larger footprints and so I often pair it with Cosmopolitan.
Polygamy - I think it's more roleplay flavor than useful. Given that you can have Concubines for most of the tribal governments, having 3 wives on top of that is a bit overwhelming. Being able to flip wives to boost stats has its uses though. It really loses it for female rulers in my experience.
Religious Tax - I just find it pointless to the point of never taking it.
Syncretism - Another more flavor than useful. Usually take it with a few religions across the whole map.
Haruspicy - It sounds cooler than it actually is. Spending Gold early in the game and then getting a moral penalty because of RNG is just a kick in the nuts. I take it on a few religions just for some flavor.
Astrology - It's decent enough to take on a fair number of religions. Having access to the Hermetic Society and getting a Zodiac sign are both worth taking.
Monasticism - Good to take on a number of Religions. +2 Learning and being able to force "Take Vows" are both good. Obviously plays well with Proselytizing for a good role play combination.
Daring - Having access to Prepared Invasions can be useful for starting out. I think it is more useful for the AI to keep things interesting. Usually have a number of religions with this doctrine. I am a bit on the fence with this one
Unrelenting - Pretty good for any aggressive religion. Maybe more true for extreme climates as attrition can be diabolical.
Sea Bound - It's probably a bit over powered. I tend to use it in smaller religions that are somewhat isolated other than having access to the sea. Sea Raiders are easily the most annoying thing in this game for me. I try to keep them to a minimum without totally removing them.
Animistic - Interesting roleplay and useful. I will have a number of Religions with this doctrine.
Ancestor Veneration - Good roleplay and somewhat useful. Will have a number of Religions with this doctrine.
Bloodthirsty Gods - It's pretty good. Great roleplay and being somewhat useful. Generally have a number of religions with this across the map.