Most of the "pagan faiths" of Europe, as far as I know, did not go on trying to convert the rest of Europe. And many who did, did so through peaceful means. It's not because Christianity got all militarized and imposed itself on the others that it becomes the only valid model, imo.
At that time, it was certainly the dominant model. These pagan faiths or other faiths like hindu and budhists where all eventually heavily prosecuted and even massacred or sold into slavery by Islam and Cristianity.
Either way, these models never where able to get along nor should they.
i'd also like to note that a feature like this should be kept simple and to the minimum, the amount of freedom for inovation and creativity should always remain.
Just some simple moderate bonuses and penalties
And perhaps give both religions one extra option for each type which only priests can use restrictedly with 50/60% oratory skill or more.
For the militant type you could perhaps instead of a region wide unrest, you could give them the option to hit a greater area of people.
With effects similiar to that of causing unrest but now on a larger scale. (hit 5 regions at the same time)
Or perhaps have the option to choose a hatred view towards a specifc religion where the effects would a dramatized version of evil, where just straight mobs are formed to masacre the members of the hated faith, cleansing certain regions brutally of the other faith. this option could also be region specifc instead of adding another kind of view.
Or the option to call upon jihad or crusade, where a region is beeing declared to be taken by a certain realm, if the realm gets the region, the realm or religion could be rewarded, or the region would be easier to takeover/maintin in the first weeks.
The other type, the less militant one could perhaps have an option to call for demonstration where everyone stops eating and working and goes on a hunger strike for a certain amount of time(droping production and morale).
Or also, an area effect but now to calm the populance/entralling populance.
Or perhaps a super preach option where when a priest preaches, it effects more regions at once.
Or perhaps temporarly reduce the amount of consumed food, like jesus deviding the food, making food consumption more eficient and showing the more richer that they are overconsuming.
just some ideas.
