Stay balanced between GAP source (Stupa, Hero worship, etc) and extracting more benefit from Golden Age modifier (Mosque, Cathedral, etc). Too much GAP source will give you too much unused GAP. Too much benefit from Golden Age will give you less value on those yields. Other than Religion, consider Chichen Itza. It's a powerful addition to ensure minimum gap between two Golden Age. Also Artistry policy.
I can see the benefit of Mosque.
Going to start inspiration/holy law (Hero worship and cathedrals as I mentioned already taken).
I get gold monopoly in 7-8 turns for more GAP.
What do you mean with "Too much benefit from Golden Age will give you less value on those yields." ?
I've looked at Artistry and not convinced it's that good with a wide authority play but considering it for a change.
It will mean less food to work those specialists and just less food in general compared to Fealty and means no Taj Mahal.
I can sort of see the Artistry players are those saying that you don't need many tiles for a city....
The lack of Fealty food will affect resettling of conquered cities since growth will be much slower (with fealty food a new city grow to size 4-6 in that number of turns), the Satrap's Court on the other hand allows for keeping cities thanks to generating gold compared to the normal upkeep cost of courthouses (now there's just the crappy location settled).
Faith buying will not get the reduced cost (compared with Fealty) which affects choices like Mosque.