One of the main problems (if we consider this a problem) that the developers of RFCV have is the limit number of civilizations per game: 22 civilizations and 41 city-states. Civilization V has got 34 civilizations by now, so there will be missing something like 12
12 really important civs like Sweden, Ethiopia, Korea
I have one idea that may be useful to finish with that problem.
Rhye is now developing a version to vanilla. I think he must do that so people who do not have Gods and Kings are able to play RFC. But people that bought GaK and DLC will see the game diversity consubstantially reduced. Thats why I had the idea to create not one RFC but tree RFC: RFC 3000 BC; RFC 300 AD and RFC 600 AD. If this idea is adopted, there will be room for all the civilizations because civilizations that appear in RFC -3000 do not appear in RFC 300. The same happens between RFC 300 and RFC 600. Some less important civilizations like Austria that do not have room in RFC -3000 can appear in RFC 600 occupying the room left by ancient civilizations. The most important civilizations like England, China, India, America, etc., will appear in all the games. Why these dates? The first one is the regular starting year of RFC. In 300 AD were the first European invasions and in 600AD began the second ones. There is lots of geopolitical trouble in these years so the world stage changes consubstantially between 3000BC and 300AD as well as between 300AD and 600AD, making room for new nations and destroying others.
This idea works fine with only two RFCs (-3000 and 600) but if there is made another DLC, the new civilizations will have no room or will take room to some very important civilizations. Thats why there should be tree different maps, with different conjugations of civs.
There is one problem in the conjugation: will Polynesia and the Huns appear or not? They were not nations but a group of people with the same culture. They should not be included or only be included if there is room available, in my opinion.
There is a group of 16 civilizations that will appear in all the games: America, Arabia, Aztecs, China, England, France, Germany, India, Japan, Turkey, Russia, Mongolia, Spain, Incas, Denmark and Ethiopia. They are the core of the game. Without these important civs, RFC does not exist. After these civs, there will be 6 more per game. 16+6=22, the limit number. 16+3x6=34, the number of civs In civ V. As I removed the Huns and Polynesia, Netherlands appears twice as well as Korea.
My list of civilizations in order of appearance (S=starting civilization):
RFC 3000 BC
[Focus: classical era]
1- Egipt (S)
2- Babilonia (S)
3- India (S)
4- China (S)
5- Greece (-1900)
6- Rome (-753)
7- Persia (-678)
8- Cartage (-650)
9- Japan (-300)
10- Ethiopia (100)
11- France (481)
12- Arabia (622)
13- Spain (718)
14- Russia (882)
15- England (927)
16- Germany (962)
17- Denmark (965)
18- Inca (1197)
19- Mongolia (1206)
20- Turkey (1227)
21- Aztecs (1376)
22- America (1776)
RFC 300 AD
[Focus: medieval era]
1- China (S)
2- Maya (S)
3- Ethiopia (S)
4- (Insular) Celts (S)
5- Byzantines (330)
6- France (481)
7- India (500)
8- Japan (538)
9- Arabia (622)
10- Spain (718)
11- Netherlands (880)
12- Russia (882)
13- Korea (918)
14- England (927)
15- Germany (962)
16- Denmark (965)
17- Inca (1197)
18- Mongolia (1206)
19- Turkey (1227)
20- Songhai (1340)
21- Aztecs (1376)
22- America (1776)
RFC 600 AD
[Focus: late medieval and renaissance]
1- India (S)
2- China (S)
3- Japan (S)
4- Ethiopia (S)
5- Arabia (622)
6- Spain (718)
7- France (843)
8- Netherlands (880)
9- Russia (882)
10- Korea (910)
11- England (927)
12- Germany (962)
13- Denmark (965)
14- Sweden (970)
15- Portugal (1143)
16- Austria (1156)
17- Inca (1197)
18- Mongolia (1206)
19- Turkey (1227)
20- Siam (1238)
21- Aztecs (1376)
22- America (1776)
Portugal is not an official civilization but I believe it will be released soon as a DLC. If not, it could be also created a Portuguese civilization specifically for RFC (although Rhye said he would not do that). It is just one idea to improve and diversify the mod.
I also have one idea for the minor civilizations. They will not be represented by city-states but by nations that, together, cover all the land area. If a civilization enters a civil war, the cities are distributed by the nations where they belong. For example, if Russia becomes independent, some cities can go to Poland, others to Ukraine, etc.
The minor civs are not confined to one city, they are able to have many cities, and they can found cities as well (in less number than the playable civs). The relationships work as equal as in the regular game but with one difference. To talk to the nation you click in any city belonging to it. Than there are the gold tributes, which should be higher (the nations are bigger) and the ally benefits. The benefits when you are ally work fine in my opinion but you can not receive all the luxury and strategic resources. If you are ally you receive only two luxury resources and one strategic resource (with mercantile you receive 2+X strategic resources, according to the number of porcelain or jewels they have).
There is also another minor faction, the invading barbarians, which can capture cities and maintain barbarian kingdoms.
Minor civs appear in two ways: a civilization that has cities in the land covered by a minor civ collapses. In that case the minor civ receives the cities and begins to play; or the minor civilization reaches the starting year and begins such as the major civs, but with one settler or one city taken from a major civ. Some of the minor civs, like the Franks, have no starting year, meaning that they only appear if a civilization (France, for instance) collapses.
List of city states by game:
RFC 3000 BC
Europe: Continental Celts (-800, militaristic); Ukraine (cultured); Norway (850, maritime); Poland-Lithuania (1025, cultured); Franks (militaristic); Castille-León (religious); Papal States (religious); Austria-Hungary (1156, militaristic); Anglo-Saxony (400, militaristic); Bizantines (330, religious); Ireland (1171, maritime); Netherlands (880, mercantile); Sweden (970, maritime); Portugal (1143, mercantile).
North America: Confedracy (militaristic); Canada (1867, cultured); Mexico (1821, Religious); Mayas (-2600, religious); Native Americans (S, cultured)
South America: Brazil (1822, maritime); Colombia (1819, cultured); Argentina (1916, Maritime)
Africa: Bantu (-1000, cultured); Kush (-1070, mercantile); Mali (1230, mercantile); Songhai (1340)
Asia: Australia (1901, maritime); Khmers (802, mercantile); Mongolian Tribes (-209, militaristic); Maurya (cultured); Tibet (610, religious); Iran (mercantile); Japanese clans (S, maritime); Korea (918, cultured); Siam (1238, cultured)
Middle East: Hittites (-1800, militaristic); Assyria (934, militaristic); Phoenicia (-1200, mercantile); Arabian Emirates (mercantile); Hebrews (-1030, religious)
RFC 300 AD
Europe: Ukraine (cultured); Norway (850, maritime); Poland-Lithuania (1025, cultured); Franks (militaristic); Castille-León (religious); Papal States (religious); Austria-Hungary (1156, militaristic); Anglo-Saxony (400, militaristic); Ireland (maritime); Sweden (970, maritime); Portugal (1143, mercantile); Belgium (1831, cultured); Lombardia (568, Militaristic); Venice (697, Mercantile); Scotland (militaristic); Burgundy (411, mlitaristic)
North America: Confedracy (militaristic); Canada (1867, cultured); Mexico (1821, Religious); Sioux (S, cultured); Olmecs (S, Religious); Iroquois (1450, cultured)
South America: Brazil (1822, maritime); Colombia (1819, cultured); Argentina (1916, Maritime)
Africa: Bantu (S, cultured); Fatimids (909, religious); Mali (1230, mercantile); Berbers (1040, militaristic)
Asia: Australia (1901, maritime); Khmers (802, mercantile); Mongolian Tribes (S, militaristic); Delhi (cultured); Tibet (610, religious); Iran (mercantile); Japanese clans (S, maritime); Siam (1238, cultured)
Middle East: Seljuks (1037, militaristic); Arabian Emirates (mercantile); Israel (1099, religious)
RFC 600 AD
Europe: Ukraine (cultured); Norway (850, maritime); Poland-Lithuania (1025, cultured); Franks (S, militaristic); Castille-León (religious); Papal States (religious); Hungary (895, militaristic); Anglo-Saxony (400, militaristic); Ireland (maritime); Belgium (1831, cultured); Lombardia (568, Militaristic); Venice (697, Mercantile); Scotland (militaristic); Prussia (militaristic); Bohemia (870, cultured); Italia (1861, cultured); Switzerland (1291, cultured)
North America: Confedracy (militaristic); Canada (1867, cultured); Mexico (1821, Religious); Sioux (S, cultured); Mayas(S, Religious); Iroquois (1450, cultured)
South America: Brazil (1822, maritime); Colombia (1819, cultured); Argentina (1916, Maritime)
Africa: Bantu (S, cultured); Fatimids (909, religious); Mali (1230, mercantile); Berbers (1040, militaristic)
Asia: Australia (1901, maritime); Khmers (802, mercantile); Mongolian Tribes (S, militaristic); Delhi (cultured); Tibet (610, religious); Iran (mercantile); Japanese clans (maritime).
Middle East: Seljuks (1037, militaristic); Arabian Emirates (mercantile); Israel (1099, religious)
The minor civilizations can appear in a late game as well as the major civilizations to keep the game dynamic.
Hope you liked the idea.