Sid Meier said it is extremely important to narrow down options as far as possible wherever possible. If the game contains too many customizations the gamer will feel like he is the creator of the game or that the game is unfinished.
Interesting philosopy. However, despite narrowing down these options, in practice the latter does not feel to be true to me in every case.
For examples I have played those Firaxis games with various gaming experiences:
Civilization 3: I played it a few times, but I did not really liked it a lot. I am not sure why. Maybe because the graphics were not good enough and the user interface was very clumsy. I moved on to Civilization 4 when it came available.
Civilization 4: I played it a lot. I really like the game. I played it for months, then play something else, after that returning. Repeating this cycle many times. Add ons like the bug mod, which gives more options enhances the game play to me, not feeling the game is unfinished. Graphics, sounds, and music are a lot better than Civilization 3.
Railroads: I played all scenario's, it was different than Railroad Tycoon 3; more cartoonyish. I like the game element of multiple tracks and switches, but I felt it was poorly implemented by my taste. Eventually I discovered OpenTTD which has more options to lay complicated tracks. To me this is a better experience.
Pirates: This is a game which I agree most on with this philosophy. It is a simple game, while staying challenging and fun. Graphics, sound, and music are good enough. There are many mini games like navigating, trading, treasure hunting, sea warfare, land warfare, fencing, dancing, and simple fleet management. As an allrounder one the of best games ever made.
Civilization 5: Expecting more of Civilization 4, this is a disappointment. It is something different than Civilization 4. It's an ok game on it self, but not what I am looking for. I played it a few times and then moved on to play Empire: Total War which is a hybrid game consisting of an even more simplified Civilization and a RTS in the Total War series style.