Things haven't gone quite so rosily for me, in part because I haven't played Monarch in a long time (nor much Civ at all), in part because the RNG gods haven't been especially friendly, and in part because some of the AI are actually playing decently well.
My first target was the Mongols, whom I denied Iron early enough that they had only one Swordsman. They gave me enough tech to convince me to fight the Zulu a bit instead, though in retrospect the Zulu would have been more useful as an ally against Sumeria than conquered. So I switched back and forth conquering those two for awhile, finishing off Mongolia first with an overwhelming force of Med Inf and Pikemen. I, too, had significant flipping problems, having only one Temple for culture plus the Temple of Artemis when I controlled Karakorum.
The going got tough against Mongolia. My plan was to upgrade my 30-40 Knights to Cavalry and then trounce them, but they jumped the gun and invaded me first. But their lack of Saltpeter and Horses hurt them, and my Knights broke their stacks of pikes, longbows, Ancient Cavalry, and archers. I waited until Cavalry to go on the offensive, and took three cities in one turn, razing two (the other having J.S. Bach's). By this time, however, the Sumerians had started trading and had both Saltpeter and Horses (Cavalry and Musketmen). Bach's flipped back, but I built cities replacing the other two and made peace for tech. 20 turns later I again took three cities at once, this time against defending Riflemen, and as all three had worthwhile wonders, none were razed. The current struggle is to keep the cities from flipping while my culture is 1/8 the Sumerian, and razing the other Sumerian cities nearby with any extra troops.
On the other continent, the Celts destroyed the Byzantines quite early, the French not too long afterwards, and recently the Japanese. No doubt I will have a great final struggle with the Celts. They're also more advanced than I, so it will be a good war. I'm thinking I'll have to send lots of bombers and tactical nukes over to flatten them out.