I would use a fixed seed, then make a map from scratch. Only use wine hill squares for trade as it has the best food/production/trade output. If you only build cities where you can get all 4 resources, then you should have either wine or gold for moneys. the other squares should have like 1 or 2 hills, then all grassland. Fill all squares with river and your trade will be uber with democracy, or republic. More so with democracy, no corruption
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