Units Revisions

Civilization’s ‘units’ need to be revised. Some revisions have been needed ever since earlier games, because Civ has never gotten the sequence of early gunpowder development right, or the historical relationship and sequence of Knights, Pikemen and Spearmen correct. Other revisions are needed because currently, Civ V has an Upgrade path for spearmen/pikemen that is a complete crock and no Upgrade path at all for Scouts, which is almost equally bogus.

In addition, whle G&K added the possibility of getting ‘Unique’ units from Militaristic City States, they still leave out a number of interesting and useful Unique Units that could be available by City State to add variety to the game.

Finally, there are some Units that will become available not only because of Technology, but also because of Social Policy: knights, Heroic Warriors (Aristocratic) are obviously tied to the Social Policies of Military Elite, Honor, Warrior Code, etc.

Here is a set of suggestions for revision of the current Civ V/G&K Unit Set. Completely new units or renamed units or revised factors are shown in Italics.

Ancient Era:
Scout (Recon).....................................CS – 5, R – 0, M – 2, Cost – 25, Gold – 140
Warrior (Melee)...................................CS - 8, R – 0, M – 2, Cost – 40, Gold – 200
..Jaquar (Aztec Melee)..........................CS – 8, R – 0, M – 2, Cost – 40, Gold – 200
..Maori Warrior (Polynesian Melee).........CS – 8, R – 0, M – 2, Cost – 40, Gold – 200
Spearman (Anti-Mounted Melee).............CS – 11, R – 0, M – 2, Cost – 56, Gold – 260
..Pictish Warrior (Celts) ........................CS – 11, R – 0, M – 2, Cost – 56, Gold – 260
..Hoplite (Greek).................................CS – 13, R – 0, M – 2, Cost – 56, Gold – 260
..Battering Ram (Huns).........................CS – 10, R – 0, M – 2, Cost – 75, Gold – 320
..Immortal (Persia)..............................CS – 12, R – 0, M – 2, Cost – 56, Gold – 260
Archer (Ranged).................................CS – 5, R – 7/2, M – 2, Cost – 40, Gold – 200
..Bowman (Babylonian Ranged).............CS – 7, R – 9/2, M – 2, Cost – 40, Gold – 200
..Slinger (Incan Ranged).......................CS – 4, R – 7/2, M – 2, Cost – 40, Gold – 200
..Atlatlist (Mayan Ranged).....................CS – 5, R – 7/2, M – 2, Cost – 36, Gold – 180
..Rhodian Slinger (City State)........CS – 5, R – 7/2, M – 2, Cost – X, Gold – X
..../+25% Ranged Factor against other Ranged Units
..../Available from City State: Rhodes
Chariot Archer (Mounted Ranged).........CS – 6, R – 10/2, M – 4, Cost – 56, Gold – 260
..War Chariot (Egyptian).....................CS – 6, R – 10/2, M – 5, Cost – 56, Gold - 260
..Horse Archer (Hun)..........................CS – 7, R – 10/2, M – 4, Cost – 56, Gold - 310
..War Elephant (Indian).......................CS – 9, R – 11/2, M – 3, Cost – 70, Gold - 310
Noble Warrior (Mounted Melee)....CS – 12, R – 0, M – 3, Cost – 70, Gold - 310
..../ONLY buildable with both Copper Resource and
......Social Policies of Aristocracy, Honor and Warrior Code
Trireme (Naval Melee)........................CS – 10, R – 0, M – 4, Cost – 45, Gold – 225
..Dromon (Byzantine).........................CS – 8, R – 10/2, M – 4, Cost – 56, Gold – 260
..Quinquireme (Carthaginian)...............CS – 13, R – 0, M – 4, Cost – 45, Gold – 220

Classical Era:
Swordsman (Melee)............................CS – 14, R – 0, M – 2, Cost – 75, Gold – 390
..../Promote from Warrior
..Mohawk Warrior (Iroquois).................CS – 14, R – 0, M – 2, Cost – 75, Gold – 390
..Legion (Roman)................................CS – 17, R – 0, M – 2, Cost – 75, Gold – 390
Composite Bowman (Ranged)...............CS – 7, R – 11/2, M – 2, Cost – 75, Gold - 320
..../Promote from Archer
Horseman (Mounted Melee)..................CS – 12, R – 0, M – 4, Cost – 75, Gold – 390
..../Promote from Noble Warrior
..Cataphract (Byzantine)......................CS – 15, R – 0, M – 3, Cost – 75, Gold – 390
..African Forest Elephant (Carth)...........CS – 14, R – 0, M – 3, Cost – 100, Gold – 480
..Companion Cavalry (Greek)...............CS – 14, R – 0. M – 5, Cost – 75, Gold – 390
..Numidian Horseman (City State)..CS – 7, R – 10/1 M – 5 Cost – X Gold – X
..../Can Move after Ranged Combat
..../Available from City State: Cirte
Catapult (Siege).................................CS – 7, R – 8/2, M – 2, Cost – 75, Gold - 390
..../50% penalty against Units
..Ballista (Roman)..............................CS – 8, R – 10/2, M – 2, Cost – 75, Gold – 390
..../50% Penalty against Units

Medieval Era:
Man at Arms (Melee)..................CS – 21, R – 0, M – 2, Cost – 120, Gold - 460
..../Promote from Swordsman
..Berserker (Denmark)........................CS – 21, R – 0, M – 3, Cost – 120, Gold – 550
..Samurai (Japan)..............................CS – 21, R – 0, M – 2, Cost – 120, Gold – 460
..Jomsborg Viking (City State)..............CS – 21, R – 0, M – 3, Cost – X, Gold – X
..../Requires 1 Iron
..../Amphibious Promotion, When embarked, can attack other units at sea
....../(Melee attack = 8)
..../From City State: Jomsborg
Pikeman (Anti-Mounted Melee)..............CS – 16, R – 0, M – 2, Cost – 90, Gold - 370
..../25% Combat penalty fighting in Hill, Forest, Marsh, or Jungle tiles
..Landsknecht (German).......................CS – 16, R – 0, M – 2, Cost – 45, Gold – 220
..../25% penalty fighting in Hill, Forest, Marsh, or Jungle tiles
..Swiss Pikeman (City State).........CS – 16, R – 0, M – 2, Cost – X, Gold – X
..../Ignores Terrain Penalties for Hills
..../Available from City State: Berne
Crossbowman (Ranged)...................CS – 13, R – 18/2, M – 2, Cost – 120, Gold - 460
..Cho-Ko-Nu (Chinese)....................CS – 13, R – 14/2, M – 2, Cost – 120, Gold – 460
..Longbowman (English)..................CS – 13, R – 18/2, M – 2, Cost – 120, Gold – 460
Knight (Mounted)...........................CS – 20, R – 0, M – 4, Cost – 120, Gold - 460
..../Available with No Maintenance from Castle Improvement
..Camel Archer (Arabia)..................CS – 17, R – 21/2, M – 4, Cost – 120, Gold - 460
..Keshik (Mongolia)........................CS – 15, R – 16/2, M – 5, Cost – 120, Gold – 460
..Naresuan’s Elephant (Siam)...........CS – 25, R – 0, M – 3, Cost – 120, Gold – 460
..Mandekalu Cavalry (Songhai).........CS – 20, R – 0, M – 4, Cost – 110, Gold – 430
..Conquistador (Spain)....................CS – 20, R – 0, M – 4, Cost – 135, Gold – 500
Trebuchet (Siege)..........................CS – 12, R – 14/2, M – 2, Cost – 120, Gold - 460
..../50% penalty against Units
..H’wacha (Korean)........................CS – 11, R – 26/2, M – 2, Cost – 120, Gold - 460

Renaissance Era:
Dragoon (Recon)....................CS – 15, R – 0, M – 4, Cost – 150, Gold - 500
..../Promote from Scout
..../Ignore terrain costs
..../+2 Sight range
NOTE: Has Scout-like Sight and no terrain penalties, and because they dismount to fight Pikes/spears have no advantage against them
Arquebussier (Melee).............CS – 22, R – 0, M – 2, Cost – 120, Gold - 450
..../Promote from Man at Arms
NOTE: The first ‘Gunpowder’ melee infantry. Slight improvement in combat factors,
but actually cheaper than the heavily-armored infantry they replace
..Musketeer (France)......................CS – 28, R – 0, M – 2, Cost – 150, Gold - 540
..Janissary (Ottomans)...................CS – 24, R – 0, M – 2, Cost – 150, Gold – 540
..Tercio (Spain).............................CS – 26, R – 0, M – 2, Cost – 160, Gold – 570
Fusilier (Melee).....................CS – 30, R – 0, M – 2, Cost – 180, Gold - 600
..../Promote from Arquebussier or Pikeman
..../+ 50% Bonus versus Mounted
NOTE: The classic smoothbore musket-carrier with socket bayonet: Not only much better combat factor than Arquebussier, but bonus versus Mounted
..Minuteman (America)..................CS – 28, R – 0, M – 2, Cost – 150, Gold – 540
..Carolean (Sweden)......................CS – 30, R – 0, M – 2, Cost – 180, Gold – 600
..Hessian Fusilier (City State)...CS – 30, R – 0, M – 2, Cost – X, Gold – X
..../+1 Production in City when used as Garrison
..../Available from City State: Darmstadt
NOTE: Because 18th century troops were given about half their time off, when they could get jobs - big boost to the workforce in a city in which they were stationed
Galloper Gun (Ranged)............CS – 20, R – 20/1, M – 3, Cost – 180, Gold - 620
..../Promote from Crossbowman
..../If suitable terrain available, 80% chance of retreat from Melee
..../50% Penalty versus cities
NOTE:The lightest of artillery, fires cannister to short range.
Low combat factor, but can retreat before combat
Cuirassier (Mounted)...............CS – 25, R – 0, M – 4, Cost – 185, Gold - 640
..../Promote from Knight
NOTE: The armored cavalry that replaced Knights.
..Sipahi (Ottomans).........................CS – 25, R – 0, M – 5, Cost – 185, Gold – 640
..Hakkapeliitta (Sweden)..................CS – 25, R – 0, M – 4, Cost – 185, Gold – 640
Bombard (Siege).....................CS – 12, R – 18/2, M – 2, Cost 160, Gold - 600
..../Promote from Trebuchet
..../50% Penalty versus Units
NOTE: The weapon that made Castles obsolete.
Cannon (Ranged/Siege)...................CS – 14, R – 20/2, M - 2, Cost – 185, Gold - 640
..../Promote from Bombard
NOTE: First Siege Unit with no penalty against Units
Galleass (Naval Ranged)..................CS – 16, R – 17/2, M – 3, Cost – 100, Gold - 400
Caravel (Naval Melee).....................CS – 20, R – 0, M – 4, Cost – 120, Gold – 600
..Turtle Ship (Korean)......................CS – 36, R – 0, M – 4, Cost – 120, Gold – 600
Frigate (Naval Ranged)....................CS – 25, R – 28/2, M – 5, Cost – 185, Gold - 770
..../Requires 1 Iron (Industrial Quantity)
..Ship of the Line (English)...............CS – 30, R – 35/2, M – 5, Cost 170, Gold – 720
..../Requires 1 Iron (Industrial Quantity)
Privateer (Naval Melee)...................CS – 25, R – 0, M – 5, Cost – 150, Gold – 650
..Sea Beggar (Netherlands)..............CS – 25, R – 0, M – 5, Cost – 150, Gold – 650 Captures enemy ships

Industrial Era:
Armored Car (Recon)...............CS – 50, R – 0, M – 5, Cost – 350, Gold - 1050
..../Promote from Dragoon
NOTE: Late Industrial: deadly against Barbarians or pre-gunpowder troops
Rifleman (Melee)............................CS – 34, R – 0, M – 2, Cost – 225, Gold - 740
..../Promote from Fusilier
..Norwegian Ski Infantry (Denmk)......CS – 34, R – 0, M – 2, Cost – 225, Gold – 740
..Mehal Sefari (Ethiopia)...................CS – 34, R – 0, M – 2, Cost – 200, Gold – 680
Gatling Gun (Ranged)......................CS – 36, R – 36/1, M – 2, Cost – 225, Gold - 740
..../Promote from Galloper Gun
Cavalry (Mounted)...........................CS – 34, R – 0, M – 4, Cost – 225, Gold – 740
..../Promote from Cuirassier
..Hussar (Austria)............................CS – 34, R – 0, M – 5, Cost – 225, Gold – 740
..Cossack (Russia)...........................CS – 34, R – 0, M – 4, Cost – 225, Gold – 740
Artillery (Siege)..............................CS – 21, R – 28/3, M – 2, Cost – 250, Gold - 800
Ironclad (Naval Melee).....................CS – 50, R – 0, M – 3, Cost – 250, Gold - 800
..../Requires 1 Coal (Industrial Quantity)

Modern Era:
Great War Infantry (Melee)...............CS – 50, R – 0, M – 2, Cost – 320, Gold - 960
..Foreign Legion (France)..................CS – 50, R – 0, M – 2, Cost – 320, Gold – 960
Infantry (Melee)..............................CS – 70, R – 0, M – 2, Cost – 375, Gold - 1090
Machinegun (Ranged).....................CS – 60, R – 60/1, M – 2, Cost – 350, Gold - 1030
Landship (Mounted)........................CS – 60, R – 0, M – 4, Cost – 350, Gold - 1030
..../Requires 1 Oil (Industrial Quantity)
Tank (Mounted).............................CS – 70, R – 0, M – 5, Cost – 375, Gold – 1090
..../Requires 1 Oil (Industrial Quantity)
..Panzer (Germany).......................CS – 80, R – 0, M – 6, Cost – 375, Gold – 1090
..../Requires 1 Oil (Industrial Quantity)
Marine (Special)............................CS – 65, R – 0, M – 2, Cost – 400, Gold – 1140
Paratrooper (Special).....................CS – 65, R – 0, M – 2, Cost – 375, Gold – 1090
Antitank Gun (Special)....................CS – 50, R – 0, M – 2, Cost – 300, Gold - 920
..../Promote from Machinegun
Antiaircraft Gun (Special)................CS – 50, R - /2, M – 2, Cost – 375, Gold - 1090
Destroyer (Naval Melee).................CS – 55, R – 0, M – 6, Cost – 375, Gold - 1090
Battleship (Naval Ranged)...............CS – 55, R – 65/3, M – 5, Cost – 375, Gold - 1090
..../Requires 1 Oil (Industrial Quantity)
Aircraft Carrier (Naval Melee).........CS – 50, R – 0, M – 5, Cost – 375, Gold - 1090
..../Can carry up to 3 Triplanes, Fighters or Bombers
NOTE: Because the WWI era bombers were way too fragile to handle carrier landings
Submarine (Naval Ranged).............CS – 35, R – 60/3, M – 5, Cost – 325, Gold – 980
Triplane (Air Fighter).....................CS – 0, R – 35/5, M – 2, Cost – 325, Gold – 980
..../Requires 1 Oil (Industrial Quantity)
Gotha Bomber (Air Bomber).....CS – 0, R – 50/6, M – 2, Cost – 325, Gold – 980
..../Requires 1 Oil (Industrial Quantity)
Fighter (Air Fighter).......................CS – 0, R – 45/8, M – 2, Cost - 375, Gold - 1090
..../Requires 1 Oil (Industrial Quantity)
..Zero (Japan)...............................CS – 0, R – 45/8, M – 2, Cost - 375, Gold – 1090
..../Requires 1 Oil (Industrial Quantity)
Bomber (Air Bomber).....................CS – 0, R – 65/10, M – 2, Cost – 375, Gold - 1090
..../Promote from Gotha Bomber
..../Requires 1 Oil (Industrial Quantity)
B-17 (America).............................CS – 0, R – 70/10, M – 2, Cost – 375, Gold – 1090
..../Requires 1 Oil (Industrial Quantity)

Atomic Era:
Helicopter Gunship (Special)............CS – 60, R – 0, M – 6, Cost – 425, Gold - 1190
..../Promote from Armored Car
..../Requires 1 Aluminum (Industrial Quantity)
..../Bonus versus all armor/Mounted
Rocket Artillery (Siege)..................CS – 45, R – 60/3, M – 2, Cost – 425, Gold - 1190
Mobile SAM (Special).....................CS – 65, R – X/2, M – 3, Cost – 425, Gold - 1190
Atomic Bomb (Bomb).....................CS – 0, R – X/10, M – 2, Cost – 600, Gold – 1550

Information Era:
Mechanized Infantry (Melee)............CS – 90, R – 0, M – 3, Cost – 375, Gold - 1090
Modern Armor (Mounted)................CS – 100, R – 0, M – 5, Cost – 425, Gold – 1190
..../Requires 1 Aluminum (Industrial Quantity)
Missile Cruiser (Naval Ranged).......CS – 80, R – 100/3, M – 7, Cost – 425, Gold - 1190
Nuclear Carrier (Naval Melee)....CS – 80, R – 0, M – 7, Cost – 500, Gold - 1350
..../Promote from Aircraft Carrier
..../Requires 1 Uranium
..../Can carry up to 4 of any aircraft, bomb or missile, including Nuclear
Nuclear Submarine (Naval).............CS – 50, R – 85/3, M – 6, Cost – 425, Gold - 1190
..../Can carry up to 3 missiles of any kind
Jet Fighter (Air Fighter)..................CS – 0, R – 75/10, M – 2, Cost – 425, Gold - 1190
..../Requires 1 Aluminum (Industrial Quantity)
Stealth Bomber (Air Bomber)..........CS – 0, R – 85/20, M – 2, Cost – 425, Gold - 1190
..../Requires 1 Aluminum (Industrial Quantity)
Nuclear Missile (Bomb)..................CS – 0, R – X/12, M – 2, Cost – 1000, Gold – 2270
Guided Missile (Bomb)...................CS – 0, R – 60/8, M – 2, Cost – 150, Gold - 540

Future Era:
Mobile Infantry (Melee)................CS – 100, R – 0, M – 3, Cost – 500, Gold – 1350
..../Ignores terrain costs
..../+3 Sight
NOTE: Enhanced infantry with personal armor, stealth tech, personal drones,
Exo-skeleton, heavier weaponry.
Orbital Weapons (Ranged)..............CS – 0, R – 120/4, M – 2, Cost – 500, Gold - 1350
..../Can carry additional 2 missiles, including Nuclear
NOTE: Drop big stuff on anything: replaces Artillery of all kinds, land or sea.
Maneuverable Satellite, can be moved to any tile and use conventional or nuclear weapons from there.

Possible Additional Promotions:
Sapper I........Melee Units
....................Can build Roads
....................Prerequisites: To Be Determined
Sapper II........Melee Units
.....................Can build Forts
.....................Prerequisite: Sapper I
Ranger I..........Melee, Ranged Units
......................Prerequistes: To Be Determined
......................No Movement Terrain Penalty in Forest or Marsh
Ranger II..........Melee, Ranged Units
.......................Prerequisite: Ranger I
.......................No Movement Penalty in Hills or Jungles
Ranger III..........Melee, Ranged Units
........................Prerequisite: Ranger II
........................Moves normally through Mountain tiles

Tying units to social policies would indeed be nice.

What's obviously missing is a mounted Renaissance unit (Dragoon, Cuirassier), same as a crossbow upgrade (maybe a Falconet?). An Industrial-era Dreadnought, of course. A more versatile upgrade for the Machine Gun, too (maybe APC or AFV). There also should be a light naval line that can outrun the heavier ships: sloop/gunboat, patrol/torpedo boat, etc. And scout upgrades, my goodness! Something like explorer, balloon, airship, recon plane, spy drone would suffice.

mdl5000 said:

Tying units to social policies would indeed be nice.

What's obviously missing is a mounted Renaissance unit (Dragoon, Cuirassier), same as a crossbow upgrade (maybe a Falconet?). An Industrial-era Dreadnought, of course. A more versatile upgrade for the Machine Gun, too (maybe APC or AFV). There also should be a light naval line that can outrun the heavier ships: sloop/gunboat, patrol/torpedo boat, etc. And scout upgrades, my goodness! Something like explorer, balloon, airship, recon plane, spy drone would suffice.

Click to expand...

We can end up with an almost infinite number of units, many of which were not used for much, or only in special circumstances, historically. A good example would be the balloon, which was either a tethered, stationary recon device of zero use in a war of movement or a specialized light transport (as in the Siege of Paris).
The best 'balloon' to add to the game would actually be the Zeppelin or Airship: a WWI Bomber type with a small bomb load, very vulnerable to fighters, but massively extended range compared to the "Great War Bomber".

As for a 'light naval' unit, the problem is that the current Caravel - Frigate - Destroyer units all represent the 'scouting' vessels of their eras: doesn't leave a lot of room for another 'scout' on the sea.

I tried to come up with historical units/weapons that would give a good set of upgrades in places where they were now missing:
Scout (Ancient Era) - Dragoon (late Renaissance) - Armored Car (Late Industrial Era) to Helicopter

Spearman (Ancient Era) - Pikeman Medieval Era) - Fusilier (late Renaissance Era) where the advent of the bayonet makes all 'infantry' pretty much identically musket armed.

Crossbowman (Medieval Era) - Galloper Gun (late Renaissance Era) -
Gatling Gun (Industrial Era) - Machinegun (Modern Era)
...The Machinegun units of WWII really became included in the Mechanized Infantry of the post-war, late 20th century: Ranged units in game terms all got much longer range - like artillery or airpower.

As for air reconnaissance, most of the 'spy planes' up until the present have been converted or specialized fighter or bomber airframes, then satellites, while the modern 'drones' are better included as greater sight range for ordinary units, since they are rapidly miniaturizing to the point where they can be carried by an ordinary soldier - the "Mobile Infantry" (thanx to Heinlein for the designation) of the Future Era I proposed.

Social Policy units and perhaps buildings would be very interesting- it might make focusing on Social advancement feel a bit more game-changing like Scientific advancement does.

It would be fun to see combinations of policies from different trees and how they would interact- perhaps even some World Wonders could be unlocked in this way.

Galgus said:

Social Policy units and perhaps buildings would be very interesting- it might make focusing on Social advancement feel a bit more game-changing like Scientific advancement does.

It would be fun to see combinations of policies from different trees and how they would interact- perhaps even some World Wonders could be unlocked in this way.

Click to expand...

Everything should interact to some extent: Access to certain Resources certainly makes a difference in the units you can build already, but many units were based as much on Social/Cultural traits as on resources - how else to explain the difference between a Celtic swordsman and a Roman Legionairy?

We already have some Wonders dependent on things like city position (build only on seacoast, only near mountain, only near desert, etc), but why not increase the interactions? How can any civilization build, or even start, a 'religious' wonder like Notre Dame or the Great Mosque if they haven't founded a Religion yet? The Brandenburg Gate memorialized military victories: if you haven't ever captured a city from an enemy Civ, how could you build such a Wonder?

Right now, Wonders are simply objects of Building Races among civs. They should represent the culmination of a chain of events, decisions, and situations, some of which the player will have only partial control over in any single game. That, I think, would make them a lot more Wonderful when you were able to build them...

I agree that tying Wonders more to what has happened would make them feel more important- would there be less Wonders available to build, but with more impact from each wonder?

How many Wonders would become available for a player intent on getting as much of them as they can?

If Wonders were more restricted, their effects could possible be strengthened to be a defining part of a civilization, rather than just a bonus on the side.

Out of curiosity, what requirements would you place on the Hanging Gardens wonder?

I like all of your ideas. The unit upgrade path is a bit quirky right now. Why not have multiple upgrade options for units which you could do in Civ IV? Swordsman can upgrade to pikemen or longswordsmen (though I much prefer the label of man at arms as you suggested) and pikemen can upgrade to musketmen or lancers.

Unique Citystate units would be amazing and give some needed life into the current military city states.

More prerequisites for wonder and unit construction would definetly shake things up. Some off the top of my head:

Hanging Gardens: requires a fresh water source and/or X population in a city
Terracota army: requires a great general/admiral to have been spawned
Statue of Zeus: currently control a city you did not found
Oracle: city on a hill
Great Wall: X number of barbarian units destroyed
Great mosque of Djenne: on or adjacent to desert tile
Alhambra: requires X number of knights built
Taj Mahal: must have completed X golden ages
The Porcelain Tower: must have completed X research agreements
Big Ben: must currently have X luxury resources
Statue of Liberty: Must have spawned X great people
Eiffel Tower: requires X iron resources
Pentagon: X number of units currently owned

I was perusing the suggested unit upgrade tree, and I noticed that Chariot Archers and the Unique Units derived from Chariot Archers have no upgrade path.

Was that intentional?

mintcandy said:

I was perusing the suggested unit upgrade tree, and I noticed that Chariot Archers and the Unique Units derived from Chariot Archers have no upgrade path.

Was that intentional?

Click to expand...

That was left out - Chariot Archers should upgrade as they do now, to Knights or their equivalent.
I would love to have an alternate path of 'mounted missile' units, but it would involve a branching upgrade path, since not all cultures used mounted missile troops - they were, for instance, always a 'scout' option in western Europe after the fall of the Roman Empire.

Right now, most of the Civs that get Chariot Archers and used mounted missile troops later (Mongols, Arabs) can upgrade to their Unique Units - but not all.

One possibility, which has the advantage that it is historically accurate, would be to allow Chariot Archers to upgrade to Horsemen, which could either stay Horsemen and upgrade to the 'advanced scout' Dragoon in the Renaissance, or upgrade to the Knight/Knight-equivalent as they do now. That would approach the flexibility we need in mounted upgrades that is missing now: many civilizations that had access to mounted skirmishers or mounted missile troops simply lose them after Chariot Archers become obsolete.

Okay, after a minimum of thought...
Here are some sample 'Social Policy Effects' towards building units, or moving your Civ towards certain units:

Liberty (Ancient Era)
....Citizenship
+25% Tile Improvement construction rate
Free Worker appears near the capital
+10% Bonus when building Spearmen
Required to build Hoplites
.....All:
Free Great Person of your choice near the capital
+10% Bonus towards any Freedom Policies
Tradition (Ancient Era)
......Aristocracy
+15% when building Wonders
+1 Happiness for every 10 citizens in a city
Required for Noble Warrior
......Landed Elite (Legalism)
+10% Growth and +2 Food in capital
+10% Bonus when building any Horseman or Knight
......All:
+15% Food Growth and free Acqueduct in first four cities
-25% to any Foreign Religion Influence or Conversion.
Honor (Ancient Era)
......Honor
+33% Combat Bonus against Barbarians
Notification of new Barbarian encampments in revealed territory
+ Culture for each Barbarian killed.
Required for Noble Warrior
......Warrior Code
+15% Production when building Melee Units
Great General appears near the capital
Required for Noble Warrior
......Discipline
+15% Combat Strength for military units with military unit in adjacent tile
Required for Legion
......Military Caste (Discipline)
+1 Local Happiness, +2 Culture for each garrisoned city.
-10% cost for any Knight, Samurai unit
......All:
Grants Gold for each enemy unit killed.
+10% Bonus towards any Autocracy Policies
Piety (Classical Era)
Cannot be active at the same time as Rationalism
.....Theocracy (Organized Religion)
+10% Gold output in city with Temple
Units purchased with Faith do not count agains Unit Limit
Patronage (Medieval Era)
.....Cultural Diplomacy (Scholasticism)
+100% Resources from City States
+50% Happiness from gifted Luxuries
-10% cost for any Scout, Dragoon, or Armored Car unit
Commerce (Medieval Era)
.....Merchant Navy (Naval Tradition)
+3 Production in all coastal cities
+10% Gold from any Naval Trade Route
Freedom (Renaissance Era)
Cannot be active at the same time as Autocracy or Order
.....Universal Sufferage
+33% Combat Strength in each city
+ 25% Limit on Unit totals
Autocracy (Industrial Era)
Cannot be active at the same time as Freedom or Order
.....Militarism
-33% Gold cost to purchase units
Required for Panzer

When combined with bonuses for certain Technology research from Resources and position, this should be a beginning at 'pushing' civilizations into certain directions. None of it is designed to be Absolute: you can research in any direction you want, it's just going to be easier if the research matches your civilization's needs and resources:

If you have Horses, researching Horseback Riding will be easier, and if you have Horseback Riding and Social Policy: Landed Elite, you'd be a fool not to build a bunch of Horsemen, unless your chief opponent is across a bunch of Jungle tiles...