On the research front, I went for Printing Press before Education, thinking to power up villages and towns. This turned out to be a mistake - William beat me to Liberalism. :( He took Nationalism, which meant I had to drop Education and go for that instead to get the Taj Mahal. I was confident that my crazy hammer capital could beat William to the wonder, with the Marble from my colony.
Also in the tech department, here's an effect I hadn't foreseen. The presence of all the colony vassals had a serious effect on the AIs' willingness to trade techs. For each AI, getting past "We're not ready to trade this" is measured as a percentage of civs in the game that know the tech. With more civs in the game (but completely nonviable as far as economic entities), the viable researching civs accounted for a much smaller percentage, so most techs had to get around to almost all of the AI civs before any would trade to me. I presume this worked the same for AI-AI trades as well, though.
So with a number of courthouses in place (mostly whipped), I've finally gotten enough EPs to see the demos on all the major players. Here's the GNP graph, where I'm doing well but William is going nuts! Well, this game is not really going to be a tech race; we're planning on the diplomatic exit.
And here's the power graph, where I'm expectedly last, and Caesar is running away. I hope he doesn't get any ideas...
Yeah, nobody saw that coming. Oh wait, I think I just did. And yes, that's Caesar declaring war at +8 Pleased relations.
The timing on this is oh so close to being oh so much better. 6 turns to go on the Taj Mahal. With it, I can make a free switch to Nationhood and defend anywhere necessary by drafting. Well, I'll try to hold out and rely on whips for now. Fortunately I got past my period of completely neglecting defense; most of the carracks with settlers set out without escort, but I'd shipped longbows almost everywhere by now.
I sent Guilds to Suleiman to get help in the war, and finally sold my world map to everybody to get cash for upgrading a couple key defenders. Amusingly, the war gives me free "mutual military struggle" diplo merits with my colonies.
Rome, inexplicably, attacked at three separate locations at once, with insufficient force to capture any of them. His "main" stack landed on the southern island, two praets and four catapults, where I'd kept reasonably reinforced with two longbows in each city. Caesar also landed single galleon loads on both my mainland and westernmost island - a praet and two catapults each - all easily repelled by whipping a defender and upgrading another. (The BTS AI really seems to go heavy on the siege units. But they can't kill defenders, so all you need is more bodies, even warriors, than the AI has regular unit attackers, and you can't lose.)
Killing off the invaders spawned two Great Generals (thanks Imperialistic), and both settled in my capital. Really nothing else to do with them - I had no plans to go conquering so didn't need any Medic III, and the Heroic Epic is already cranking military units like crazy so no need for a Military Academy.
Rome would now talk peace, offering 470 gold for the privilege. I had noticed a couple workers on the shore of Rome's tundra city, so I had loaded a few units onto a galleon. Before making peace, I swooped in to swipe three workers. Ha ha! And that raised the price of peace to Drama (750 beakers) plus 100 gold.