It doesn't need a generic orientation, I never think to myself in the game 'need to run an SE/CE' here. Instead I look at the land available and try to make one Bureaucracy commerce city, a few specialist cities, a few production cities, etc. I aim to have decent numbers of GPP, strong commerce, ability to make lots of units/buildings quickly, etc. All these things help to win a game. And of course if I end up with lots of cottage cities I will be more likely to go for free speech/emancipation, just as if I have many high food sites caste system/representation will be more desirable. The point is there's no need to decide at any point on one rigid economy style, rather play the map and leader and do whatever will maximise the strengths available from either.