I believe that these problems stem directly from the decision to make civ V a one-unit-per-tile (1UPT) game. 1UPT allows a lot of flexibility in how you arrange your army; however, it only works if your army has empty space to move in. It requires an army smaller than the map. 1UPT led to small army sizes, which led to lower production and faster science, which led to the broken economy system that this game has now. The combat in civ V was based on panzer general, but that doesn't work well in a civ style game. I tried to explain why that is in this post:
http://forums.civfanatics.com/showpo...0&postcount=48
Clearly this was a decision made early on, since it's such an important part of the game. At the same time, they wanted to keep the "civ" feel to the game, where you settle new cities, build improvements and city buildings, and go in to the city screen to adjust your citizens. Combined, this meant that they had to limit the total number of tiles in the game, and so they tried to force army sizes to be very small. A typical civ 4 army of ~50 units would be incredibly annoying to manage in the Civ V style, so they wanted to encourage armies of only 5~10 units. I hope this succession game showed how clunky warfare becomes in this game when the army sizes get large (I enjoy the early wars with small army sizes). The AI can't handle it, and the player doesn't enjoy it.
In order to do that, they had to limit production. You can see that in the decreased yields- production and food yield have been decreased compared to civ 4, whereas the food required to grow a city was greatly decreased. The early units like warriors don't take very long to build, but the cost of units quickly increases. The high upkeep costs for units, buildings, and roads factor in to this as well (see my sig). The idea was, I think, that every new military unit would take about 10~20 turns to build, just enough to replace your losses while you continually upgraded your original army. As a result, your army size would stay almost constant throughout the game.
Also, it's worth pointing out that there's two ways of effectively decreasing production. Either decrease hammer yields while increasing costs- which they did- or to make science go faster- which they also did. The beaker cost of techs decreased, great scientists became more powerful, and research agreements were added. All of these accelerated the tech pace, giving less time to build the units/buildings for each technology, which effectively decreased production.
So now the developers are stuck with a game that has greatly reduced production values. That's fine, except for one thing- what do they do in the early game? They can't expect us to just sit around clicking "next turn" for 40 turns waiting for our worker to finish, or 100 turns for a library to finish. It's bad enough that it already takes up to 15 turns to finish that first worker. So, they had to make the early stuff a bit cheaper. You can build a warrior in ~6 turns, and you can build a horseman or a library in ~10. Even a coloseum only takes ~20. The idea was that a small city was efficient enough to produce the early game stuff in a reasonable amount of time, and as the city grew, it would produce the later stuff in the same amount of time- keeping army size constant while the cities grew and built infrastructure. There would be no massive increases in the power of a city with its size (like civ 4 had) because if a city became really powerful, it could create huge armies which would break the 1UPT system. If large cities were only modestly more powerful than small cities, the army sizes would stay small. That's pretty much what I discovered when I tried a game limited to just 3 large cities, which I describe here
http://forums.civfanatics.com/showpo...8&postcount=37.
What the developers overlooked was that we're not limited to just a few large cities- we can build as many small cities as we want! Granted, we're limited a bit by happiness, but there's a lot of ways to solve that little problem (like keeping the city size small). And since small cities are so efficient at building the early game stuff, and large cities never become vastly more powerful, the many small cities with their trading posts (even without any multipliers) will quickly outproduce the large cities with their mines, despite their forges and workshops.
The game is in an awkward situation where large cities can't be too good because it would imbalance the middle and late game, but small cities have to be good or else the early game would be boring. And of course science is shared between all cities, so the more cities you have, the faster science goes, without any corresponding increase in city production. The result is what we've got now- a large number of small, undeveloped cities can produce a collossal amount of gold and science, which allows us to outtech even a large deity AI, while producing anything we want.
I know a lot of people will suggest balance tweaks to fix this. But I don't think this can be solved adequately without somehow addressing the issue of 1UPT at civ scale. You can't give an incentive to make large, developed cities better because that will just make that late game even faster and more unit-clogged than it is now. You can't make small, undeveloped cities weaker because than the early game will just be excruciatingly slow and boring.
(But I don't get how this question relates to our discussion 
)
