Not sure how set_convert_other_groups is supposed to work, but with Unyielding, Civilized, Stability and Autocephaly my vassals were happily converting the Orthodox, Catholic and Sunni land that they conquered.
Unyielding ("Nature" is the one that matters) is set to
(It's listed as 'defensive' in the features file).
"1", according to the wiki and the settings in the default religion files, means that AI characters with high zeal will attempt to convert it, but low zeal will not. Zeal is a composite setting based on traits - a zealous mastermind theologian has high zeal, whereas, say, a cynic has low zeal.
Before Holy Fury (or for players without Holy Fury), unreformed pagans were '0' to non-pagans (never try) and '2' to fellow pagans (always try). Reformed pagans were 2/2 (always try to convert anyone; the standard for Christianity, Islam, and Mazdan).
Post Holy Fury, the settings are
Peaceful: 0/0
Warlike: 0/1
Defensive(Unyielding):1/1
Proselytizing: 2/2
Dogmatic:0/2
Cosmopolitan:0/0
(First is other group, second is same)
So out of the six types,
- two are never-convert-anyone-anytime, which is less than any religion including unreformed pagans (a pretty unuseful setting from a game standard, unless your goal is to have a chinese-style kingdom, but you wouldn't get the benefits of it)
- two will never convert non-pagans, making the player do aggressive work in any civilized part of the world and many less-civilized (much of the steppes is Buddhist or Mazdan)
- one is 1/1, which is still less aggressively religious than either judaism or the indian religions (1/2 and 2/1 respectively, though the order is written backwards in the religion file)
- and only proselytizing is a standard reformed religion (Christianity, Islam, Mazdan, all reformed pagans without Holy Fury).
The way the numbers work practically is to make most of the reform options extremely tedious for the player; more tedious than any real world religion except unreformed pagans. In two of six choices reform makes spread essentially impossible, as only the player will ever convert any provinces.
Yeah, I think whoever was looking at it wasn't thinking about total game balance, and instead was just worried about making custom religions too strong. I actually have a degree in game design, and that's an error that lots of people I've worked with are prone to. Interesting thought that you can use Jizya as an exploit, though...
Peaceful: 1/1
Warlike: 1/1
Defensive(Unyielding):1/1
Proselytizing: 2/2
Dogmatic:2/2 (Dogmatic should *obviously* want to convert their own realm; proselytizing other realms is covered by other settings)
Cosmopolitan:1/1 (Honestly the reduction to cosmopolitan should be more that it fails to convert rather than zealous characters not functioning as zealous - the logical thing would be just to increase the MTTH on conversions).
I feel like that's an error they made with all of them - the special boosts don't seem to actually include all of the effects of the two included reforms, when you look at events and decisions.
Yes, you can.