Yes and holy sites should also generate passive spread, making their location more strategic. Cities spread should be weaker than holy sites.
Holy sites are twice as strong at passive spread than cities and the holy city is either 1.5 or 2x holy site ... but passive spread is fairly weak until it is used in conjuntion with missionaries and inquisitors.
I like the idea of limiting the number to holy sites to some degree but prefer the different layer approach although that would stop you being able to kill them and killing them not only removes their useless bodies from your sight but also removes their religion.
Some good findings that should clarify other discussions (see link at end)
Missionaries are very good at converting atheist cities and are much cheaper than apostles and got earlier. They are your initial rush and convert troops and later convert unconverted outlying unconverted cities. They are useless at converting something that is already religious. They do make good scouts.
Apostles are for converting already religious cities, they are useless at converting atheists in comparison to missionaries. They are also your combat troops and will attract enemy apostles like fly paper if you sit them on a holy site. Their promotions are varying in value, I tend to not promote early ones or promote them to useless promotions so I can save the good promotions until later because the promotion bug still looks in place. An Apostles fighting prowess is not at all dependent on charges so I go out and convert and then fight with 1 charge left.
Inquisitors are my favorite. they will attract an apostle so the apostles damage the inquisitor and get damaged themselves. The damaged apostle has less conversion power but enough will convert my city which is fine. I then use one charge of my cheap inquisitor to remove what they have done. Damaged or not, the religion is removed like it says on the box. I am quite happy for them to send 20 apostles in to convert all my cities as long as I have a few inquisitors around and sitting in cities so they do not fight means the city defends better also... Never use apostles in defense is my view... a few cheap inquisitors in cities is much better. Then when you gain a city send one off to remove the other religion... they also put some of your religion into it and with passive spread this is enough for small cities, larger cities follow up and inquisitor with a missionary as they are better with atheist cities. A few inquisitors with a war steamroller and the world is yours.
So spam out those missionaries as soon as, converting a 1 pop city means it should mostly grow just with your religion and ends up being much harder for them to convert later. Use your first apostle to start and inquisition, once you have some inquisitors they are welcome to convert my whole empire, I can just quickly remove their lies at a fraction of the cost. Now look at getting the apostles out there to convert key cities taking into account passive pressures so they are used more effectively but leave them with 1 charge to fight with if you want. Then consider making a holy war at 50% warmonger, take their cities, use inquisitors to convert them and then give them all back so by the end of the war you have no warmonger penalties and their cities are all converted. Your passive spread power has also now increased dramatically.
The real fight is where the civs are that do not have a religion and at city states. These areas tend to have a bit of messing around.
That's my take on religion, its not hard... its a shame we cannot have an armada of apostles.... that would be scary... the holy trinity of death.
Some good info in
https://forums.civfanatics.com/threads/finding-my-religion.606648/ go to the last page
In reality
@Browd should try and finish his religion guide to clear it all up
I don't think killing a religious unit with a military unit does reduce the religious influence. Beating it with another religious unit does reduce said influence.
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