I also recently tried a new crazy but safe strategy as
Earth
Aztecs
4 civs
Emperor level
I also restart game until Russia is in game since this is a bit more challenger than AI Romans.
Mainly my idea is, I wanna expand quickly but I also want to be safe enough so that I can win about 8 or 9 times out of ten and not rely on early luck against Barbarians.
You know, starting of the game building a settler is just a coin toss, if you get barbarians when you have 2 empty cities you can easily get busted. So, I instead do this to get quickly out of the starting blocks. Firstly the best spot for the Aztecs Capital for this strategy is one hex east of starting location. City no.2 is placed 2 hexes east of Capital, yes on the mexican peninsular for easy defence.
Do this when you start...
1) Move one hex east. Build Capital. Build settler, found extra City 2 tiles east of Capital. The new city is used as breeding cattle i.e. i only make settlers form that new city keeping it small so it does not cannibalise on my capital good hexes.
2) sell Palace for 200 cash!
3) build baracks and use some cash to speed it up!
4) Capital now only produces veteran chariots for a while and use them to safe up your new cities. To get a good guarantee you need at leist 2 chariots close to your capital so that a barbarian raid cannot with luck wipe out your Capital out. Most new cities produce settlers and since you do not have a palace it makes even more sense. A city can get maximum 1 trade when you have no Palace sop try to get a lot of cities early.
5) Use settlers to build cities, NOT roads. Roads wont give you any trade since you do not have Palace.
6) Build Pyramid once you have around 4 cities and 4 chariots.
7) Switch to Democrazy, now you do not need any Palace anymore
8) Build roads like crazy now and if u planned ahead you should also have built irrigation so that when you get Democrazy you can get ultra speed tech.
9) Get Religion and build Bachs Cathedral
10) Get Railroad
11) Make sure you have as many settlers as cities roughly so that you can build railroads quickly and get economy exploding.
12) When you build your first railroads prioritise and build links between cities first to get your defence system better. This allows you to call units far away for fighting off barbarians. After cities are linked prioritise building railroad on production hexes first instead of food hexes
13) Once you get industrialisation switch all cities to building factory except for those that do not have a temple yet.
14) Set taxes to 100% for a while to speed up factory building by buying them off! They will pay off enormously giving you faster completion of all other improvements
15) Get hoover dam
16) When building wonders, make use of caravans to speed it up
17) Some cities have very low production due to mostly grassland and few shields. Pick some poor grasslands (those without shields) and build forest on them. This works very well with the railroad bonus.