Well my requests for the next CIV could be summed up in this list:
1) There should be an option so Cities could develope in different ways than the fat cross. The fat cross is unrealistic. A city should start as it is right now, with 9 squares, and then expand only one square at a time with the maximum distance from the main city being 5 squares, to expand to a point you would need culture and sometimes roads, and the maximum squares a city can ocuppy would be 20, as it is now.
2) Civilisations usually arise after the city - state stage. I would like to see this implemented in a future civ.
3) Culture should spread in different ways. Monumements and religions represent culture. If your style of culture is the same with a rival you get bonus on diplomacy, and it is easier for their citizens to be assimilated to your civilization. When you conquer a city buildings built before your arival should still contribute to that nation's culture. Forts, rivers, music, movies, epics, religion all should bne taken into account.
4) Political borders.
5) Forts should also provide the following bionus: if a unit is fortified into a fort, it is considered to know the area around it better and depending on the civics it can: produce gold (sustain itself) at the price of not being as effective (-20% stength), gain extra combat power in the area 2 squares around the fort (+25% strength) as it knows where to make a fight where to lead an ambush etc), be a prison (-25% war weariness if you have 1 fort/ city), other options that I have not yet thought of.
6)Allow great prophets to create a scism in religion to create a sub religion like orthodox/ catholic church of christianity, sunits ans shiits of muslim, etc.
7)Allow imigrants from war, culture or other reasons. They could be used acording to your civics. Examples include but are not restricted to: after conquewring a city taking part of the population and sending it to another city of yours where it wil integrate in your civillisation faster, while sending some from your pure civilians in that city (to raise the percentage of people from your empire), to capturing part of the popultaion of a city to be used as slaves in your city, to people willing to join your empire because of its more humain constitution or lesser inflation rating (economical refugees).
8) an option to play with quantitative resources
9) ability to build bridgies and dams but also to create canals.
10) military units are civilians given weaponry and proper training. Creating soldiers should use food as well as production. Disbanding soldiers should provide some food.
11) barbarian cities that exist long enough become city states then minor civilisations.
12)war weariness should also depend on what city produced what unit. If you send a unit from city A to war but no units from city B city A gets more war weariness than city B. Thus if one city has all the military production, it would make sense that that city should also get some buildings to keep her happy about sending her chieldren to be slaughtered.
13) cities requesting buildings to be built (provided that Ai does not demand completely stupid things like this city needs a coloseum when the city is at population 3 and does not even have a forge) and if you switch your production to that you get +1 happy + x hammers per turn to complete it.
14)making pilliaging and sieges more interesting by: a)cutting trade routes with a unit give money the first turn you do so, equal to the amout that the trade route would give its owner b) if a city is completely cut off ( all 8 squares around it blocked), it looses 1 pop per turn and all units loose a percentage of their strength every round, in additon to the current bombardment system.
15) better automated workers. At the moment they tend to do oh so many useless things. Give us options to prioritise what they should do, like I do not want cottages if the square will latter be usefull for improvement X.
16)narcotics, slavery, porn, gambling and all those "vilain" things are a potent market. They are a form of
resources unless your civics are against them. If not too politicly incorect for a game they should somehow be implemented.
17)espionage could also bribe leaders not to try to improve their country as it now happens in the third world.
18)Option to start without any characteristics on your civilisation and get them as time passes by, through your choises of aggresiveness, building culture and by factors such as the climate you live in etc.
19)Future technologie should be added based on current research being done on subjects such as exploiting nuclear fision, creating highscraper cities that add to the maximum population a city can have, create cerebral implants that allow to control machinery through thought etc.
that's all for now folks