Finished my later save game of Japan (save J1 one above), turned out to be more challenging than expected. Spoilers following if you are playing that J1 save above. I actually expected A1 to be more challenging, and it will be interesting to compare Culture victory times when I finish A1. Thing is Australia is a thing. The gossip kept saying they are going for culture victory, yet they kept conquering city states and other civilizations (like the Cree and later Persia). Really pisses me off that John Curtin is such a hypocrite. He says he doesn't like warmongers, yet he is one himself. I love civ6 over Civ5 in nearly every way, but one thing Civ5 did better was peaceful civs were actually peaceful civs, where warmongering civs were actually warmongering civs. You could expect aggression from Mongolia and Zulu. In civ6 you can easily get in alliances with those civs. The civ personalities in Civ 6 need work.
As I said, Australia was a thing, they really kept conquering cities. Eventually they stopped once the only other civ on their continent was Rome, who was also quite strong. John Curtin actually finished with a higher score than me, which is the first time that has ever happened in a King level game.
I will eventually finish my A1 save above in post #2, probably tomorrow, and I would like to compare win times. Japan is a civ I love, and I don't mind playing them more than once. Even though I don't consider them that strong, at least not for my play style.
My ranking for A1 save is Catherine the Great #6. Turn #500. I forgot to build government district in my capital, and hence national history museum. I like to build that in my capital with art museum and Reyna fully promoted. Not sure if it would have made much difference. Events in game made building government district in my capital not feasible, at least not in a timely manner.
You are almost tempting me to play again, I know I can do better. And not be lazy and plan my cities and districts better. As strong as their bonuses can be, they still have trouble competing against civs like Australia. I really can't rank them above a C+ because of their slow culture victory times. Part of this is my fault for not micromanaging enough, but for my play style that's what I rank them as. Perhaps they are better suited for space victory, not culture victory. Since you are building factories anyways because of the electronics factory. I'm tempted to play again going for science victory. They are ill suited for cultural victory in my opinion. Their factory comes too late to provide enough culture to power you through.
Looking at my other save games for civ of the week, this has been my slowest cultural victory other than Egypt which was one difficulty level lower (that was a Prince game). I really can't say they are well suited for Cultural victories at this point. I kind of want to try them for science victory. They have to be better at that than cultural victory. Sadly, this was my 2nd slowest time.
I did manage to build Petra in a city next to Delicate Arch. Which is one of my favorite natural wonders only because I've actually been there. The AI wasn't in a hurry to build Petra, and I managed to snag it (though I still had to trade route stack to get it). Sadly, I couldn't get Huey, despite this being a good map for it.