Awesome read Sullla, thanks a lot.
By the way, are the old 'exploits' from Civ 3 still there to any degree? Can you still get a right of passage, move all your troops next to their cities, and then declare war? Even if the diplomatic consequences are very bad, this is still the most efficient way of wiping a civ out if you're the most powerful in the world.
How about the mass upgrade trick? I know most players considered this a viable strategy, but I thought it was a bit stupid. If I remember properly you can build a lot of low-tech units for less shields, but only BEFORE you research the higher tech. I mean, if this is a viable strategy, why shouldn't you be able to build low-tech units later on, just because your technology is more advanced? It just seems a very artificial way of turning gold into shields. IMO upgrading a unit should require it to sit in a city and get 'rebuilt' with shields (for a slightly lower shield cost and retaining its experience).