Delnar_Ersike
Prince
Let me cut down on wall of text. It's still going to be long, just not super-long
Re start bias: yeah, forgot that Mongolia was plains bias. Plains bias is nice for salt, but horses are guaranteed if you're playing with Strategic Balance (which I assume you are). Given Civ5's patchy terrain generation, start biases outside of tundra don't dictate most of the lands around your capitol if you're at 4 or 5 billion years: I've seen Arabia's Desert start bias place them near a 4 tile desert surrounded by grassland, and I've seen Poland's plains bias place them next to 3 plains surrounded by grasslands and desert hills. A plains start bias on strategic balance does not mean access to more horses than a desert start bias or an avoids forest start bias.
Can't comment much on the impossibility to found religions on Deity: the AI gets so many yield bonuses at that point that you're almost playing a different game entirely. OP said they were going Immortal or Emperor though, and founding religions really requires a good faith start at those levels, meaning Desert Folklore is even more important (since you can't get religion from improvement faith pantheons, eg. quarry faith).
Re horseman taking damage from unit: AI cannot move and attack in the same turn and cannot attack with a military unit that is stacked with a garrisoned unit (AFAIK), so there's no danger of getting hit by a newly produced unit if the city already has a garrison. I factored in Tradition's damage bonus and extra strength from hills; without Oligarchy, it's around 75-80 damage, and without hills, it's about 75 damage. Without the garrisoned unit giving the city some bonus strength, it's also 75-80 damage (easiest scenario of no garrison, no Oligarchy, flat terrain is around 65 damage, 10-15 without the crossbow). Barring high rolls and terrain defense penalties, it's highly unlikely that a full HP horseman will die in a single turn from a garrisoned city in early Renaissance. This is all, of course, assuming that the AI gets no strength bonuses at higher difficulty levels; I don't think it does, but I thought I'd mention this just to be sure.
Re multiplayer thing: I just thought I'd mention it, I admit that what I said doesn't apply to non-simultaneous combat. But yes, simultaneous combat makes a huge difference: unless you have the element of surprise, your opponent will be waiting for you to move your keshiks into range and immediately clickspam their ranged units to fire back before you get the chance to submit your retreat move. You'll get your first attack move off before taking damage, maybe your second from Logistics as well if you're quick with hotkeys, but it's fairly rare that you'll get your retreat move off before they get their ranged retaliation attacks off. At that point, fragility matters, and Keshiks are unfortunately quite fragile, especially once your opponents get into Renaissance and early Industrial.
Re speed difference and economy talk: it's not as clear of a difference. Remember, Keshiks with Khans have lower strength than Camels. For those turns before you get logistics, a force of 5 Camels will deal as much damage as 6 Keshiks; this translates into being able to take a city 1-2 turns earlier with camels. If speed is as crucial as you say, then even this little difference should be taken into account. You also should not discard unit and building maintenance: when speed is of the essence, you can afford negative gold even less. Just like how the power of Keshiks is boosted even more by Khans being able to keep up with them, the power of Camels is boosted by the extra gold you'll have to afford their maintenance cost and the upkeep of their conquests.
Re Liberty outperforming Tradition lategame: the map you showed does not look like Standard Size, 8 players, 16 CS. On Standard size, you just reach Rationalism too slowly with Liberty unless you manage to capture key culture wonders, and you often don't have the room to expand properly either unless you take out one of your neighbors very early, but that falls under "snowballing". Liberty doesn't make your 13 cities incredible, it just lets you get to 13 cities early on; once you're in the lategame, it's the 13 cities that are helping you primarily, not Liberty itself (vs. Aristocracy, Monarchy, Landed Elite, and free Aqueducts), Liberty just enabled you to snowball into 13 cities with the help of early bonuses. Most of Liberty's lategame science penalty comes from completing Rationalism slower, getting GS slower (because GSP are spread out over several cities instead of concentrated in four), completing science buildings slower because each individual city has less hammers than a 4-city tradition player's individual cities, and reaching science building techs slower due to slower Rationalism. Of course, Liberty with Rationalism still beats Tradition without Rationalism in science. I guess the difference becomes a lot more apparent when your opponents reliably rush Rationalism just like you; thankfully, it's fairly easy to make the AI do this via [conditional] flavor edits.
Re Piety: 3 fillers is not impossible, even without Oracle. If you're in a position where you can make use of Glory to God or Jesuit Education, it's often worth it to delay a Rationalism policy by a point to pick those up: your science will perform better with those Reformation beliefs unlocked than having access to Free Thought 20 turns earlier, since you can insta-build Public Schools and Research Labs with faith and/or purchase GS with faith for key academies and/or sooner bulbs.
Re Patronage: I don't find the gold bonus from reduced spending on CS influence that useful, but it might just be me. If I really need the gold, I'd rather go into Commerce; even if I'd spend gold on CS influence, I find the flexibility of a vanilla gold boost much more useful than a gold boost to only gold spend on CS influence. I cannot comment on Forbidden Palace in Deity, because, again, AI yields are so high that Deity is almost a different game, and the OP mentioned Emperor or Immortal.
Re Aesthetics on Persia: if you plan on going Aesthetics solely for the GAs, it's worth delaying working your artist guild slots until you have Aesthetics unlocked (much like if you plan on going Futurism in multiplayer). If you do this, the +25% GWAM generation represents something along the lines of 2-3 extra Great Artists at least. Although instant Great Artist pushes back your counter, it's still an instant Great Artist, which means instant Golden Age [extension].
Re Honor: Warrior Code is useful if you're evenly matched against your opponent, Military Tradition is useful if you have units that don't die quickly (so Keshiks, Camels, Longbows, Ships-of-the-Line, etc.). The former can be a lifesaver because it lets you plant Generals a lot more often, the latter is more of a "win-more", ie. it helps you win more if you're already in an advantageous position. Warrior Code is more useful for its faster Great General generation than for its free Great General, and the bonus melee unit production comes in handy for Infantry, SAMs, and Paratroopers, and XCOMs. The other problem is Military Tradition is 1 extra policy point in, which you may or may not be able to afford before Rationalism; there's little point to picking it up after Rationalism and ideologies.
Autocracy-wise, you'll probably pick up both Barracks happiness and Courthouse happiness eventually, but when choosing between the two, I'd take Barracks happiness before Courthouse happiness. Probably personal preference though, especially since Courthouses have such an obscene maintenance. The important thing to realize is that with Prora, Autocracy offers more happiness than Order, even if Order is supposedly for wide empires; the majority of Autocracy's happiness is concentrated in two tenets as well, while Order's is spread out over 4 tenets. Don't know how well it fares without Prora though, I'm guessing Autocracy is roughly even with Order, though its happiness buildings are not as essential as Order's.
Freedom can be good for constant domination, so long as you pick up Statue of Liberty and can somehow support a lot of specialists. Statue of Liberty + Secularism + Civil Society effectively makes all of your specialists have +1 food, +2 hammers, and +2 science even without their specialist yields, which can be monstrous. The caveat is that your cities must have enough population to support specialists, which usually isn't the case when you're warring constantly, but hey, it's not impossible.
Re start bias: yeah, forgot that Mongolia was plains bias. Plains bias is nice for salt, but horses are guaranteed if you're playing with Strategic Balance (which I assume you are). Given Civ5's patchy terrain generation, start biases outside of tundra don't dictate most of the lands around your capitol if you're at 4 or 5 billion years: I've seen Arabia's Desert start bias place them near a 4 tile desert surrounded by grassland, and I've seen Poland's plains bias place them next to 3 plains surrounded by grasslands and desert hills. A plains start bias on strategic balance does not mean access to more horses than a desert start bias or an avoids forest start bias.
Can't comment much on the impossibility to found religions on Deity: the AI gets so many yield bonuses at that point that you're almost playing a different game entirely. OP said they were going Immortal or Emperor though, and founding religions really requires a good faith start at those levels, meaning Desert Folklore is even more important (since you can't get religion from improvement faith pantheons, eg. quarry faith).
Re horseman taking damage from unit: AI cannot move and attack in the same turn and cannot attack with a military unit that is stacked with a garrisoned unit (AFAIK), so there's no danger of getting hit by a newly produced unit if the city already has a garrison. I factored in Tradition's damage bonus and extra strength from hills; without Oligarchy, it's around 75-80 damage, and without hills, it's about 75 damage. Without the garrisoned unit giving the city some bonus strength, it's also 75-80 damage (easiest scenario of no garrison, no Oligarchy, flat terrain is around 65 damage, 10-15 without the crossbow). Barring high rolls and terrain defense penalties, it's highly unlikely that a full HP horseman will die in a single turn from a garrisoned city in early Renaissance. This is all, of course, assuming that the AI gets no strength bonuses at higher difficulty levels; I don't think it does, but I thought I'd mention this just to be sure.
Re multiplayer thing: I just thought I'd mention it, I admit that what I said doesn't apply to non-simultaneous combat. But yes, simultaneous combat makes a huge difference: unless you have the element of surprise, your opponent will be waiting for you to move your keshiks into range and immediately clickspam their ranged units to fire back before you get the chance to submit your retreat move. You'll get your first attack move off before taking damage, maybe your second from Logistics as well if you're quick with hotkeys, but it's fairly rare that you'll get your retreat move off before they get their ranged retaliation attacks off. At that point, fragility matters, and Keshiks are unfortunately quite fragile, especially once your opponents get into Renaissance and early Industrial.
Re speed difference and economy talk: it's not as clear of a difference. Remember, Keshiks with Khans have lower strength than Camels. For those turns before you get logistics, a force of 5 Camels will deal as much damage as 6 Keshiks; this translates into being able to take a city 1-2 turns earlier with camels. If speed is as crucial as you say, then even this little difference should be taken into account. You also should not discard unit and building maintenance: when speed is of the essence, you can afford negative gold even less. Just like how the power of Keshiks is boosted even more by Khans being able to keep up with them, the power of Camels is boosted by the extra gold you'll have to afford their maintenance cost and the upkeep of their conquests.
Re Liberty outperforming Tradition lategame: the map you showed does not look like Standard Size, 8 players, 16 CS. On Standard size, you just reach Rationalism too slowly with Liberty unless you manage to capture key culture wonders, and you often don't have the room to expand properly either unless you take out one of your neighbors very early, but that falls under "snowballing". Liberty doesn't make your 13 cities incredible, it just lets you get to 13 cities early on; once you're in the lategame, it's the 13 cities that are helping you primarily, not Liberty itself (vs. Aristocracy, Monarchy, Landed Elite, and free Aqueducts), Liberty just enabled you to snowball into 13 cities with the help of early bonuses. Most of Liberty's lategame science penalty comes from completing Rationalism slower, getting GS slower (because GSP are spread out over several cities instead of concentrated in four), completing science buildings slower because each individual city has less hammers than a 4-city tradition player's individual cities, and reaching science building techs slower due to slower Rationalism. Of course, Liberty with Rationalism still beats Tradition without Rationalism in science. I guess the difference becomes a lot more apparent when your opponents reliably rush Rationalism just like you; thankfully, it's fairly easy to make the AI do this via [conditional] flavor edits.
Re Piety: 3 fillers is not impossible, even without Oracle. If you're in a position where you can make use of Glory to God or Jesuit Education, it's often worth it to delay a Rationalism policy by a point to pick those up: your science will perform better with those Reformation beliefs unlocked than having access to Free Thought 20 turns earlier, since you can insta-build Public Schools and Research Labs with faith and/or purchase GS with faith for key academies and/or sooner bulbs.
Re Patronage: I don't find the gold bonus from reduced spending on CS influence that useful, but it might just be me. If I really need the gold, I'd rather go into Commerce; even if I'd spend gold on CS influence, I find the flexibility of a vanilla gold boost much more useful than a gold boost to only gold spend on CS influence. I cannot comment on Forbidden Palace in Deity, because, again, AI yields are so high that Deity is almost a different game, and the OP mentioned Emperor or Immortal.
Re Aesthetics on Persia: if you plan on going Aesthetics solely for the GAs, it's worth delaying working your artist guild slots until you have Aesthetics unlocked (much like if you plan on going Futurism in multiplayer). If you do this, the +25% GWAM generation represents something along the lines of 2-3 extra Great Artists at least. Although instant Great Artist pushes back your counter, it's still an instant Great Artist, which means instant Golden Age [extension].
Re Honor: Warrior Code is useful if you're evenly matched against your opponent, Military Tradition is useful if you have units that don't die quickly (so Keshiks, Camels, Longbows, Ships-of-the-Line, etc.). The former can be a lifesaver because it lets you plant Generals a lot more often, the latter is more of a "win-more", ie. it helps you win more if you're already in an advantageous position. Warrior Code is more useful for its faster Great General generation than for its free Great General, and the bonus melee unit production comes in handy for Infantry, SAMs, and Paratroopers, and XCOMs. The other problem is Military Tradition is 1 extra policy point in, which you may or may not be able to afford before Rationalism; there's little point to picking it up after Rationalism and ideologies.
Autocracy-wise, you'll probably pick up both Barracks happiness and Courthouse happiness eventually, but when choosing between the two, I'd take Barracks happiness before Courthouse happiness. Probably personal preference though, especially since Courthouses have such an obscene maintenance. The important thing to realize is that with Prora, Autocracy offers more happiness than Order, even if Order is supposedly for wide empires; the majority of Autocracy's happiness is concentrated in two tenets as well, while Order's is spread out over 4 tenets. Don't know how well it fares without Prora though, I'm guessing Autocracy is roughly even with Order, though its happiness buildings are not as essential as Order's.
Freedom can be good for constant domination, so long as you pick up Statue of Liberty and can somehow support a lot of specialists. Statue of Liberty + Secularism + Civil Society effectively makes all of your specialists have +1 food, +2 hammers, and +2 science even without their specialist yields, which can be monstrous. The caveat is that your cities must have enough population to support specialists, which usually isn't the case when you're warring constantly, but hey, it's not impossible.