After playing a ton of games, I started to feel limited. My cities could only produce so many units and my research could only go so fast (even when it only took one turn). I know that Civilization has always been a turn-based game which limits how much a player can do per turn. But why can't a city build a Library and a Theatre at the same time? Why can't cities build a Tank and a Bomber at the same time? Real-Time strategy games allow for multiple research, unit production and building construction, why not Civ 4? Instead of research one technology at a time, we should be able to choose certain technologies to research at once, while having an emphasis on one. Same should go with building a unit or city improvement. What's the point of having a city with the production power to produce two units at once, but only be able to produce one at a time?

The idea sounds good in theory, but in practice all the micromanagement will just give people headaches.