I don't have much to add. Sampsa already said it and even showed. 
I myslef long time struggled with low commerce/happiness start. Recently, I had a new look at the food. At this map you have plenty of good food spots. Basically you can have 5-6 cities with good food. Then with caste system you could have 4 Great Scientists fairly easily, and this gives a good chance to win Lib followed by producing Cuirs/Rifles/Cannons through heavy whipping using all thouse food.

I myslef long time struggled with low commerce/happiness start. Recently, I had a new look at the food. At this map you have plenty of good food spots. Basically you can have 5-6 cities with good food. Then with caste system you could have 4 Great Scientists fairly easily, and this gives a good chance to win Lib followed by producing Cuirs/Rifles/Cannons through heavy whipping using all thouse food.