I have to say, either the logic of ddd888 and mqpiffle escapes me, or they are playing a very different game than me.
I can never have too much growth. Usually by turn 100, I have 10-15 cities of level 2-3. Usually 2/3 of them are towns, there's at most one native fortress and the rest are outposts and conclaves. At that point, my towns build wells and inns like crazy, second only to the grocer line, and all conclaves have a growth spell.
I think that even my worst enemies won't accuse me of having too low of a prestige, but I never see that 'too much growth' situation.
Now, if you guys (ddd888 and mqpiffle) expand slowly, and have two-three cities with prestige in the 20s, that is just your style of play. I do not see why you insist on slowing down the game for those with a different style.
And, because I do not want to be accused of exaggerating, here are sample points from my playthroughs, Note that some of them had house rules restricting expansion, number of cities or use of sovereigns... By the way, N~G [P] means N cities with average growth G and prestige P
1. House rule - single city Turn 56: 1~8 [7] Turn 98: 1~19 [18]
2. Everything goes Turn 47: 2~6 [8] Turn 73: 10~5 [36] Turn 84 19~4 [43]
3. House rule - pacifist Turn 47: 6~3 [12] Turn 59: 8~4 [17]
4. House rule - heroes stay home Turn 43: 6~1 [5] Turn 66: 10~3 [15]
5. Standard Resoln Turn 23: 3~2 [6] Turn 57: 7~2 [13]
So tell me, where is the out of control growth? Note that I have been posting these playthroughs for months, and I have not been designing them to prove you wrong. Except for the first one, at any time my cities have an average growth of 2-5, and are mostly growing slower than I would like them to.