These are some of my thoughts. I'll put them in this thread so as to not overwhelm the 1.23 thread, where I already posted something too long lol
All civilizations alter their environments, that seems to be a defining trait as we all know. Most of the ones we are familiar with, certainly our own, are quite destructive of their environments and resources over time. However, more sustainable practices, technologies and beliefs have also been around as long as human societies have existed. I think it would great to use existing game mechanics to see how those play out, tweaking numbers and incentives/disincentives and adding some additional improvement build options.
Let's safely assume that the traditional trajectory of chopping, mining, cottages, industrial revolution, resource extraction, modern/future tech has already been pretty much planned into the game to be successful. The challenge is to create some alternatives, or just tweak things so that different pathways carry advantages/disadvantages in contrast with this 'main' pathway through the eras as long as the game lasts.
In some ways, what needs to be altered is that penalties for the traditional approach are more realistic lol, meaning stronger. Certainly most of the civilizations in the game collapsed in the real world, usually in some way connected to the devastating costs of their way of using/abusing their natural endowment of resources and the social/political consequences that followed.
Changing calculations so that resource management, landscape alteration, pollution, health, happiness all have real consequences in the game depending on choices made from the beginning (or at any point going forward in time) should be a basic approach. And throughout the eras there should be options for altering pathways that moderate the penalties or create new benefits. A civ that starts out on the traditional pathway could make a change and perhaps gain success and mitigate costs of earlier fast advancement (bad health unhappiness pollution and dissent), and a civ that starts out 'green' could change its mind and maybe leap into contention or avoid elimination.
The possibility that the traditional civ will still overwhelm and conquer the more sustainably oriented (or you could say less utilitarian) civ should always remain, but it should also be possible to hold out, survive/thrive until the benefits of alternative pathways really kick in.
Different religions have had a variety of beliefs and approaches towards the nonhuman world, including even its inanimate components. Those could have an impact on the game, as they influence tenets and civics. Without having to create new traits, civics or religions, I think we could add aspects to them that have consequences in the game depending on chosen strategies.
We could say for example that Christianity has a utilitarian approach to resources (all made for mankind) and that will have different benefits and penalties over time compared to a religion like Voudoun that has a more enchanted and less utilitarian view. Since HR has a bunch of fabulous religion choices already, its just a matter of giving each one a set of characteristics with pluses and minuses when it comes to techs, improvements and their eventual consequences for health, unhappiness, dissent as well as wealth and progress rates.
A Christian civ could 'suffer' if it goes a green way, or a nature cognizant civ could 'suffer' if it goes the traditional utilitarian way. Just examples. But then you could always change religions and gain a different set of benefits, as well as costs. There should be something less neutral about the religions/tenets when it comes to resource use and development strategy. In the real world belief systems had everything to do with relationships with and use of the natural endowment, with significant consequences.
Existing civics could be tweaked in the same way. I'm assuming that there lots of fractions involved lol, so it may not be easy to get things set up, but it is possible. Right?
Land use options: There should be a way of altering ALL landscapes except arctic, as there are in the real world. Many of these are very ancient, even altering deserts so that they are inhabitable and productive. The game already offers many options but most of them degrade the environment/resource over time. There should be alternative improvement builds that are sustainable. Some can even add value over time and as the eras advance.
Forests: not the same thing as a bunch of trees lol. They should have a random but decent chance of growing in existing plots and spreading to adjacent plots.
Forests are home to animals. The animals should spawn there as long as the forest stays intact and should be able to spread to adjacent tiles along with forests.
Camps should preserve the forest but lower the chance of animals spawning over time.
There could be a hunting preserve improvement, where the yield of animals is less to begin with but steady over time and allows animals to still spawn with fair chances and spread to adjacent squares. Hunting preserves are ancient, they should be available with Walls and require Record Keeping.
If a forest and its animals, even with camps or preserves, makes it into the later eras, the value should go up significantly because there will be a lot fewer of them, bringing in increased income and then later increased culture. If wonders increase in culture production over time, it should be possible to do this with certain improvements, like hunting/animal preserve.
Animals near humans sometimes rampage, even today lol, so if you have an elephant preserve you could add a small risk for a rampage to an improvement nearby as a random event. Or a leopard or tiger or bear eats someone or something lol
Tree farms: not the same as a forest lol, but it should provide added health and good income and production, though slightly less than a real forest. Something that shows up over time rather than in straight up hammers. Could be placed on any terrain except desert, but with the need to have access to fresh water or be improved by qanats and later irrigation. Scandinavian tree farms are as far north as the tree line, so even some of those tundra plots could have tree farms as long as there is enough moisture or access to fresh water.
Tree farms that have been around 100 years could turn into/be replaced by Prime Timber, very useful for ship building.
Fish sanctuary: Could be build in the city on a water square and not produce anything by itself but keep existing fish production sustainable and steady all through the ages, while other civ's fisheries decline over time.
Deserts: I'm not sure if you can daisy chain farms from oases already in the game but there should be a way to expand outward. Qanats are ancient Stone technology and could be placed to increase food production and daisy chained over desert squares and savannas from fresh water sources. I don't know what the value of the later irrigated farms/orchards is, but perhaps the qanat version could be slightly less productive until those other options are available. The real benefit of qanats is making harsh terrains an option for a city. It could be a building that provides the technology in the city and that then allows orchards to be built in desert squares. It should be available with Agriculture and Pastoralism.
Savannah: already improvable by pastures. They could also be improved by qanats and orchards or farms. They could also be improved with tree farms. There could also be a game preserve improvement, which allows spawning and hunting of some of those terrain using animals like leopards and deer.
Terrace: could be added to hill plots to increase food production. Terraces are used for all kinds of crops, not just rice. The type of product could depend on the base terrain and how wet it is or how adjacent to existing fresh water. They could be a good alternative to mines and quarries, especially in areas without forest.
Compost: as old as nomads learning that communal toilets at various camps throughout the year seemed to grow more useful plants lol. It could be included in Agriculture. It could be a building that holds the night soil. As time goes on the farms in cities without this building will start to decline in production and the land deteriorates, while the cities with compost continue to produce at the same rate.
Biochar: could be part of Calendar and also require Pottery and a kiln built in the city first. It could be another building that afterwards adds a bit of production to the cities farms and orchards. These farms and orchards will also continue to sustain productivity without decrease and land degradation. We should call it terra preta, or use the Tupi Guarani word for it if anyone knows what that is lol
Rotational grazing: could be another building that adds this quality to pastures. Pastures would produce less overall (mimicking the effect that comes from moving the herd) but the land and production decline wouldn't happen over time. There is probably a cool ancient word for this from some culture.
Aquaculture/aquaponics: also part of Calendar and requiring Fishing and Agriculture first. Could be built next to water source and then daisy chained out on flat terrain. And there could be an aquaculture/terrace option for hill terrains or daisy chained from them. They should add food production and health, especially for interior cities without coastal access. And they were used by ancient south american cultures even in harsh desert areas without rainfall, as long as they began near rivers or springs, so they should be buildable on all terrains.
Bee hives: produce food and income and can be built anywhere, even deserts near springs. Can be used alone. There could also be beekeeping building that will add a small productivity boost and sustainable production to the cities orchards and farms over time. Could come with Pastoralism.
The alternatives to mines and quarries and forest chopping could be a bunch of bee hives, terraces, aquaponics, tree farms, camps, preserves, and rotated pastures. Civ's will miss out on hammers but will escape land deterioration and rises in poor health, unhappiness and dissent, plus declining production over time.
Aquaponics, camps, tree farms, hunting and forest preserves should all be available on jungle terrain too, long before jungle clearance is available. People once cut down trees with stone and obsidian tools, I don't think jungle clearance should require iron working lol. It could take longer for sure, so that could be the way to distinguish jungle removal before iron working.
Even as techs advance into the far future, food production will still be basically the same, so all these early improvements are just as valuable as man reaches for space. However, unless they are done right, civ's will run into trouble meeting their basic needs.
I'm assuming that each improvement in the game has numbers for health, happiness, pollution. I think that all the versions of farms and orchards and aquaculture should start with the same cost and produce the same. However, the change comes over time. The loss of productivity and/or the increase in unhappiness unhealthy and pollution should begin to kick in as the eras advance unless the civ has built the sustainable improvement building.
The land deterioration should also kick in as the years pass. That means that even though the increase in cost or wait in time to build them was felt early in the game, as the civ's age that investment can pay off if they are lucky, play smart diplomatically and escape the stronger civ's.
Mines and quarries should have a built in time span, with some random variability. With enough time, a mine and quarry will be tapped out. This will force all civ's to avoid covering every hill with a mine early in the game, because otherwise they will run out of resources down the road. However, teaching the AI to NOT cover their civ's with mines and quarries might be tricky lol, that's where the actual modding is something I know nothing about. Ideally, having a built in code that makes civ's aware of over-extraction should prevent the 'traditional' civ's from jumping so far ahead of the 'alternative' civ's.
With Education there could be some more advanced buildings specializing in any of these sustainable industries, having a substantial but fair cost to build but giving a boost to production and culture. Later, it could provide a boost in commerce as organic production versus the fertilized industrial production.
A beekeeper upgrade/building in Horticulture could do the same. A sustainable planning building with an era appropriate name could be available with Urban Planning. An ecology building could be available with Ecology in the industrial era.
Maybe with these buildings they could produce something to be traded, a skill/knowledge product like fish or stone. As long as the trade continues, the other civ gets a reprieve from decline, but not what the buildings provide, they will still have to build their own.
As the industrial era is reached and gaining access to the techs and improvements that cause pollution are inescapable, the benefit of the sustainable early investments should become an increasing factor, while the deterioration of the non-sustainable versions should have had a real impact already. In fact, civilizations in the real world collapsed LONG before even the medieval or renaissance eras. The negative costs of the nonsustainable ways of developing should start a lot sooner than the modern or industrial eras.
We will still want to build railroads and industry etc, but especially during this era the benefits of an earlier-more expensive-more time consuming build will pay off, while the costs of the 'traditional' way will be very real. The sustainable civ might be behind the traditional civ, but things might change as they catch up due to social costs and consequences of the more 'advanced' civ with its declining land and depleting resources.
If Fertilizer boosts production for a while, that should also deteriorate with time, and fairly quickly too. And/or, cost should increase as more inputs from refining are required to get the same yield. If a civ with the sustainable buildings wants to use a building available with fertilizer, they should start suffering the same consequence, losing health and pollution benefits and paying increasing input costs.
Maybe there should be an overall boost in culture and commerce for any civ in the Industrial/Modern later eras that has invested in the sustainable versions of improvements and that still have forests and animals. These places would increasingly have value in global terms as other civ's face climate change and pollution and health costs.
If a civ has skipped all the earlier options for investing the sustainable practices, era specific versions should be available but at significantly higher cost. So, adding a compost building for example in the renaissance era should be a lot more expensive and time consuming to build than it would have been back in the ancient era. Industrial and modern era builds of sustainable options should be even more expensive and time consuming, but the increase in health happiness (and decrease in pollution and land degradation) should also be measurable and advantageous.
So, just my preliminary thoughts, so sooo many of them lol
I'm a very speedy typist and I had probably a bit too much coffee this afternoon. Thanks to anyone who actually bothers to read it all!

All civilizations alter their environments, that seems to be a defining trait as we all know. Most of the ones we are familiar with, certainly our own, are quite destructive of their environments and resources over time. However, more sustainable practices, technologies and beliefs have also been around as long as human societies have existed. I think it would great to use existing game mechanics to see how those play out, tweaking numbers and incentives/disincentives and adding some additional improvement build options.
Let's safely assume that the traditional trajectory of chopping, mining, cottages, industrial revolution, resource extraction, modern/future tech has already been pretty much planned into the game to be successful. The challenge is to create some alternatives, or just tweak things so that different pathways carry advantages/disadvantages in contrast with this 'main' pathway through the eras as long as the game lasts.
In some ways, what needs to be altered is that penalties for the traditional approach are more realistic lol, meaning stronger. Certainly most of the civilizations in the game collapsed in the real world, usually in some way connected to the devastating costs of their way of using/abusing their natural endowment of resources and the social/political consequences that followed.
Changing calculations so that resource management, landscape alteration, pollution, health, happiness all have real consequences in the game depending on choices made from the beginning (or at any point going forward in time) should be a basic approach. And throughout the eras there should be options for altering pathways that moderate the penalties or create new benefits. A civ that starts out on the traditional pathway could make a change and perhaps gain success and mitigate costs of earlier fast advancement (bad health unhappiness pollution and dissent), and a civ that starts out 'green' could change its mind and maybe leap into contention or avoid elimination.
The possibility that the traditional civ will still overwhelm and conquer the more sustainably oriented (or you could say less utilitarian) civ should always remain, but it should also be possible to hold out, survive/thrive until the benefits of alternative pathways really kick in.
Different religions have had a variety of beliefs and approaches towards the nonhuman world, including even its inanimate components. Those could have an impact on the game, as they influence tenets and civics. Without having to create new traits, civics or religions, I think we could add aspects to them that have consequences in the game depending on chosen strategies.
We could say for example that Christianity has a utilitarian approach to resources (all made for mankind) and that will have different benefits and penalties over time compared to a religion like Voudoun that has a more enchanted and less utilitarian view. Since HR has a bunch of fabulous religion choices already, its just a matter of giving each one a set of characteristics with pluses and minuses when it comes to techs, improvements and their eventual consequences for health, unhappiness, dissent as well as wealth and progress rates.
A Christian civ could 'suffer' if it goes a green way, or a nature cognizant civ could 'suffer' if it goes the traditional utilitarian way. Just examples. But then you could always change religions and gain a different set of benefits, as well as costs. There should be something less neutral about the religions/tenets when it comes to resource use and development strategy. In the real world belief systems had everything to do with relationships with and use of the natural endowment, with significant consequences.
Existing civics could be tweaked in the same way. I'm assuming that there lots of fractions involved lol, so it may not be easy to get things set up, but it is possible. Right?
Land use options: There should be a way of altering ALL landscapes except arctic, as there are in the real world. Many of these are very ancient, even altering deserts so that they are inhabitable and productive. The game already offers many options but most of them degrade the environment/resource over time. There should be alternative improvement builds that are sustainable. Some can even add value over time and as the eras advance.
Forests: not the same thing as a bunch of trees lol. They should have a random but decent chance of growing in existing plots and spreading to adjacent plots.
Forests are home to animals. The animals should spawn there as long as the forest stays intact and should be able to spread to adjacent tiles along with forests.
Camps should preserve the forest but lower the chance of animals spawning over time.
There could be a hunting preserve improvement, where the yield of animals is less to begin with but steady over time and allows animals to still spawn with fair chances and spread to adjacent squares. Hunting preserves are ancient, they should be available with Walls and require Record Keeping.
If a forest and its animals, even with camps or preserves, makes it into the later eras, the value should go up significantly because there will be a lot fewer of them, bringing in increased income and then later increased culture. If wonders increase in culture production over time, it should be possible to do this with certain improvements, like hunting/animal preserve.
Animals near humans sometimes rampage, even today lol, so if you have an elephant preserve you could add a small risk for a rampage to an improvement nearby as a random event. Or a leopard or tiger or bear eats someone or something lol

Tree farms: not the same as a forest lol, but it should provide added health and good income and production, though slightly less than a real forest. Something that shows up over time rather than in straight up hammers. Could be placed on any terrain except desert, but with the need to have access to fresh water or be improved by qanats and later irrigation. Scandinavian tree farms are as far north as the tree line, so even some of those tundra plots could have tree farms as long as there is enough moisture or access to fresh water.
Tree farms that have been around 100 years could turn into/be replaced by Prime Timber, very useful for ship building.
Fish sanctuary: Could be build in the city on a water square and not produce anything by itself but keep existing fish production sustainable and steady all through the ages, while other civ's fisheries decline over time.
Deserts: I'm not sure if you can daisy chain farms from oases already in the game but there should be a way to expand outward. Qanats are ancient Stone technology and could be placed to increase food production and daisy chained over desert squares and savannas from fresh water sources. I don't know what the value of the later irrigated farms/orchards is, but perhaps the qanat version could be slightly less productive until those other options are available. The real benefit of qanats is making harsh terrains an option for a city. It could be a building that provides the technology in the city and that then allows orchards to be built in desert squares. It should be available with Agriculture and Pastoralism.
Savannah: already improvable by pastures. They could also be improved by qanats and orchards or farms. They could also be improved with tree farms. There could also be a game preserve improvement, which allows spawning and hunting of some of those terrain using animals like leopards and deer.
Terrace: could be added to hill plots to increase food production. Terraces are used for all kinds of crops, not just rice. The type of product could depend on the base terrain and how wet it is or how adjacent to existing fresh water. They could be a good alternative to mines and quarries, especially in areas without forest.
Compost: as old as nomads learning that communal toilets at various camps throughout the year seemed to grow more useful plants lol. It could be included in Agriculture. It could be a building that holds the night soil. As time goes on the farms in cities without this building will start to decline in production and the land deteriorates, while the cities with compost continue to produce at the same rate.
Biochar: could be part of Calendar and also require Pottery and a kiln built in the city first. It could be another building that afterwards adds a bit of production to the cities farms and orchards. These farms and orchards will also continue to sustain productivity without decrease and land degradation. We should call it terra preta, or use the Tupi Guarani word for it if anyone knows what that is lol

Rotational grazing: could be another building that adds this quality to pastures. Pastures would produce less overall (mimicking the effect that comes from moving the herd) but the land and production decline wouldn't happen over time. There is probably a cool ancient word for this from some culture.
Aquaculture/aquaponics: also part of Calendar and requiring Fishing and Agriculture first. Could be built next to water source and then daisy chained out on flat terrain. And there could be an aquaculture/terrace option for hill terrains or daisy chained from them. They should add food production and health, especially for interior cities without coastal access. And they were used by ancient south american cultures even in harsh desert areas without rainfall, as long as they began near rivers or springs, so they should be buildable on all terrains.
Bee hives: produce food and income and can be built anywhere, even deserts near springs. Can be used alone. There could also be beekeeping building that will add a small productivity boost and sustainable production to the cities orchards and farms over time. Could come with Pastoralism.
The alternatives to mines and quarries and forest chopping could be a bunch of bee hives, terraces, aquaponics, tree farms, camps, preserves, and rotated pastures. Civ's will miss out on hammers but will escape land deterioration and rises in poor health, unhappiness and dissent, plus declining production over time.
Aquaponics, camps, tree farms, hunting and forest preserves should all be available on jungle terrain too, long before jungle clearance is available. People once cut down trees with stone and obsidian tools, I don't think jungle clearance should require iron working lol. It could take longer for sure, so that could be the way to distinguish jungle removal before iron working.
Even as techs advance into the far future, food production will still be basically the same, so all these early improvements are just as valuable as man reaches for space. However, unless they are done right, civ's will run into trouble meeting their basic needs.
I'm assuming that each improvement in the game has numbers for health, happiness, pollution. I think that all the versions of farms and orchards and aquaculture should start with the same cost and produce the same. However, the change comes over time. The loss of productivity and/or the increase in unhappiness unhealthy and pollution should begin to kick in as the eras advance unless the civ has built the sustainable improvement building.
The land deterioration should also kick in as the years pass. That means that even though the increase in cost or wait in time to build them was felt early in the game, as the civ's age that investment can pay off if they are lucky, play smart diplomatically and escape the stronger civ's.
Mines and quarries should have a built in time span, with some random variability. With enough time, a mine and quarry will be tapped out. This will force all civ's to avoid covering every hill with a mine early in the game, because otherwise they will run out of resources down the road. However, teaching the AI to NOT cover their civ's with mines and quarries might be tricky lol, that's where the actual modding is something I know nothing about. Ideally, having a built in code that makes civ's aware of over-extraction should prevent the 'traditional' civ's from jumping so far ahead of the 'alternative' civ's.
With Education there could be some more advanced buildings specializing in any of these sustainable industries, having a substantial but fair cost to build but giving a boost to production and culture. Later, it could provide a boost in commerce as organic production versus the fertilized industrial production.
A beekeeper upgrade/building in Horticulture could do the same. A sustainable planning building with an era appropriate name could be available with Urban Planning. An ecology building could be available with Ecology in the industrial era.
Maybe with these buildings they could produce something to be traded, a skill/knowledge product like fish or stone. As long as the trade continues, the other civ gets a reprieve from decline, but not what the buildings provide, they will still have to build their own.
As the industrial era is reached and gaining access to the techs and improvements that cause pollution are inescapable, the benefit of the sustainable early investments should become an increasing factor, while the deterioration of the non-sustainable versions should have had a real impact already. In fact, civilizations in the real world collapsed LONG before even the medieval or renaissance eras. The negative costs of the nonsustainable ways of developing should start a lot sooner than the modern or industrial eras.
We will still want to build railroads and industry etc, but especially during this era the benefits of an earlier-more expensive-more time consuming build will pay off, while the costs of the 'traditional' way will be very real. The sustainable civ might be behind the traditional civ, but things might change as they catch up due to social costs and consequences of the more 'advanced' civ with its declining land and depleting resources.
If Fertilizer boosts production for a while, that should also deteriorate with time, and fairly quickly too. And/or, cost should increase as more inputs from refining are required to get the same yield. If a civ with the sustainable buildings wants to use a building available with fertilizer, they should start suffering the same consequence, losing health and pollution benefits and paying increasing input costs.
Maybe there should be an overall boost in culture and commerce for any civ in the Industrial/Modern later eras that has invested in the sustainable versions of improvements and that still have forests and animals. These places would increasingly have value in global terms as other civ's face climate change and pollution and health costs.
If a civ has skipped all the earlier options for investing the sustainable practices, era specific versions should be available but at significantly higher cost. So, adding a compost building for example in the renaissance era should be a lot more expensive and time consuming to build than it would have been back in the ancient era. Industrial and modern era builds of sustainable options should be even more expensive and time consuming, but the increase in health happiness (and decrease in pollution and land degradation) should also be measurable and advantageous.
So, just my preliminary thoughts, so sooo many of them lol
