Well on my 4th attempt I finally got a start I was happy with and cruised to a T255 diplomacy victory.
My start was 3 city tradition, NC around turn 70 off two cities, 3rd city settled the same turn NC finished. Got to education around turn 105 ish, bulbed astronomy with oxford and hit renaissance a turn before my 7th policy (around 115 I believe). After completing rationalism left side I went patronage, aesthetics and got philanthropy with about 10 turns to go.
Managed to stay friendly with everyone the whole game except Askia, who declared on me around turn 150ish (forget the exact timing); by then I had gatlings and I fought him back without a problem before Japan, Ethiopia and Austria triple declared him all on the same turn, Japan got the lions share of his land so the rest of the game was mostly spent bribing Japan to fight Austria and Ottomans instead of me, and saving gold.
I had research agreements with Japan, Austria, Huns and Ethiopia for most of the game. Siam too but they got taken out by the huns early. I never had the cash to rush buy any of the science buildings except for a couple of universities early so I was slowed down a bit by having to slow build them; I settled 4 academies before hitting plastics and used two GS to rush the UN tech. Had to slow build the UN at the end, which took about 13 turns, since I had used my only great engineer (pisa) on a manufactury tile improvement, this in hindsight wasn't a very good idea.
Ethiopia provided me with a rather nice religion (Cathedrals, +2 happiness per garden, desert folklore). I did pop a faith rune and got an unexpected pantheon however, for which I took monument to the gods, which helped with the NC.
I got all the national wonders (except temple) + pisa, didn't go for any other world wonders.
By the end of the game I had sold just about every building except the gold and food producing ones, and sold my 170ish gold per turn to the AIs; had about 11k to spend on the final turn which was more than enough to get all the city states given most of them were already friends (pledge + aesthetics combo).
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