Since the game came out it has bothered me that the special tiles couldn't be utilised until late in the game when traditionally, those places would have been small centres of cultural/spiritual formation and activity. Unique circumstances leading to unique solutions and all that. My solution would be to have a cheap 'rural' type quarter that upgrades through the ages.

My Proposal

Ancient Age

Start with "Local Tribe" quarter unlocked:

1. Can be placed same as Nature Reserve, Resources, etc. no need for connectivity.
2. Does NOT provide starting point to add other quarters, same as Nature Reserve.
3. Exploits all FIMS. But provides NO worker slots! They live in your territory and pay tribute but are Not your tribe!
4. -2 Stability, -1 Food, and -1 Stability per adjacent quarter. For the moment, they want to be left alone.
5. Low cost, and does not increase the cost of other quarters, so should be the first  things to build in a territory. This should be prioritised for the AI and prevent them from accidentally locking themselves out of a useful pollution countermeasure late game. Players should find this helpful too.
6. Can be bought with inf on outposts.

Each following age, a tech buffs their output until they become equal to the Nature Reserve.

My problem is, I don't know how to code this. I have the mod tool downloaded and have decompiled scripts, but now I am lost. Thoughts?

The point is for them to be cheap, low yield, placeholders for the nature reserve. As such they can't be religious or give faith, but rather eventually give a spot of culture. I don't mind them having very low yields as long as they don't impact the building cost of 'proper' quarters. 

Think of it like this: There are three types of resource a territory can randomly have: Luxuries, Strategic and Terrain Features like "Big Trees" or "Crater" etc. Right now, the third type can be accidentally built over since the quarter to utilise it only comes in the very late game, but if you just brought the quarter as-is to the ancient era, cities with many Features available would choke from using them as all other quarters became too expensive to build. So we need to both bring it earlier AND minimise the effect on other quarters. As balance, the yield should be lowered.

Thoughts? 

Intresting Idea, I will try to implement it in ENC