1. Research Powerhouse
- The core is a classical combo representation and caste system. A lot of specialists due to caste system and research bonus because representation gives huge amounts of extra science;
- Bureaucracy/ free speech - support the core giving some extra commerce or Production. What to use depends on how powerful your capital is and how much towns you have;
- Free market and organized religion/pacifism - also support. Free market gives extra some commerce, organized religions helps in city development , pacifism gives extra GP.
The main drawback is the need of representation which is usually available in late-game. That's why your main objective is to build The Pyramid Wonder or to get city with it. It's not always easy - but if properly planed possible even on higher difficulty levels.
The research of Code of laws is also possible quite early (sometimes with help of The Oracle Wonder) - and core of your system is already working.
The main advantage of this combination is the best research output in the game - making your science specialists really efficient.
2. The War Government
This combination is very flexible - most of the elements are optional. The only key element is either vassalage or theocracy. You introduce other options only if need them.
When planning a short war it is enough to take the theocracy and keep the rest of the options without any changes. As I've said, the bonus XP and barracks help a lot in creating stronger army.
If the war is looking to be longer or more demanding you take other XP giving civic - so usually it is a vassalage - and enjoy a quick gain on third promotion (after initial fights) of all our units.
Only if you face the total war, or you see that war will be very long and hard, it's reasonable to change all civic to prepare for this:
- Police state - guarantying (especially with Mt. Rushmore Wonder and jails in all our cities) no war wariness and quick producing of military units;
- Vassalage + theocracy - as I've said it gives together +4 XP. With Pentagon Wonder (+2 XP) we have 3 promotions for every new unit built;
- Caste system - makes a mini-culture bomb possible. After conquering a city, when all citizens are not productive, you change them into artists. Despite of no visible culture growth when the city is resistant after stabilizing situation (end of resistance) you immanently have a nice amounts of culture generated in last few turns. That's enough to secure some of surrounding terrain and give a small defensive bonus;
- State property - minimize cost of your growing empire and gives maximum possible Production output from Workshops build everywhere.
The drawback is a cost (2x high upkeep option) and no research helping civics.
3. Quick development
Third system is based on assumption of maximizing the development. Useful if you have to like to take good position in technological race or have to rebuild after a devastating war (pillaged improvements, too low technological level, not enough important buildings in cites etc.)
- Universal Suffrage: +1 Production from every town but especially possibility to buy buildings and units by Gold makes our Production faster;
- Bureaucracy or Free Speech - support;
- Emancipation or Serfdom - first helps if we need to speed up growth of Cottages, the second if you have to have lot of improvements to build;
- Free Market or State Property - depending on situation, what you need more - the money from trade routes or extra Food, Production and lower city costs.
- Organized Religion - quite obvious, +25% to building Production helps a lot.