[Saxon]

Another option, very easy to implement, is to “stale” your first three or four turns. Just hit end turn and do not give any orders for the first few turns. While it does not change how the AI performs, it gives the human a big disadvantage. As the growth tends to be exponential, those lost turns at the start really hurt in the long run.

I regret that I do not remember who first posted this idea, as they deserve credit for such a simple fix.