I REALLY think we should acquire Currency and marketplaces before we level out the research slider. After my calculations, the immense gain in commercial value by 50 % marketplaces do by far outweigh 10 turns of extra research. We may also get a tech leader that way. When we built our 3 libraries, we can as well use them. This means research for two more turnchats, not only one. This is very key, as we plan to zero out research for gold, the ideal time to do so, would be right after getting marketplaces.
For Priapos, the gold city, I intend to complete the temple, the harbor for trading out our wines and more food/gold from the fisheries, and finally a marketplace - using a granary prebuild.
Notice the timing (8 turns for temple (mining increases 1 shield in 3 turns), population increase two turns after completion, cultural expansion then the same 10 turns later, parallelling that with harbor, which takes another 10 turns, 2 turns prior to the cultural expansion, just in time for the fisheries capture 2 turns later.
This is the plan 18-20 turns ahead (build-utilization). I also need Frankn Furter or a swordsman down for garrison duties before turn 20.
Then I plan on a granary prebuild, in case the research is at full speed for currency only, so we can get a marketplace in time before we zero out research. Marketplace, a 100 shield project, will take Priapos the time from 18-31, where I plan on logrushing that forest for the marketplace as well, speeding up the process, saving 2 turns (33-31). The marketplace will give happiness bonus alone, as we probably have traded that extra wine for some luxury in the meantime.