At 250AD, I had destroyed Bismark (with help from Monty) and crippled Issy and Gandhi. Monty was tops in power by about 25%, and my scouting revealed lots of melee units in his cities. I would have liked to have attacked Alex or Hatty next, but going through Monty's land to get to them, and then leaving myself open to a massive backstab would have been inefficient and dangerous. So I had to take on Monty right away.
I spent several turns building up my Xbow numbers, and staging all of my 30-40 units at Berlin. Berlin was right up against Monty's culture boundary, thanks to a culture bomb he had set off. It was the most logical place for him to attack when I declared war. When I declared, he followed the script perfectly. He sent several waves of 6-8 units at Berlin, and I soon pulled even to him in power by hitting each stack with a couple of combat-promoted cats and then Xbows/elephants. After a little healing, I started sending 2 stacks at his cities. Monty was a tough nut to crack. He certainly didn't go down without a fight, but his AI-brain couldn't figure out how to wipe out any of my well composed stacks of elephants, Xbows, axes, and cats (with collateral damage stupid!). I captured all of Monty's mainland cities and made peace with him and his 3 island cities in 890AD. War weariness was hot and heavy and I would finish him off quickly later when I had galleons.
Unfortunately, I completely screw up my plan when I take Theology in the peace deal with Monty. Theology unlocks Paper. I was a few turns away from a second GS that was going to bulb the remaining 40% of Astro. Now the GSs will want to bulb Paper-Education-PP. Stupid Shannon! I'll have to finish Astro myself and hope I can stay afloat financially. Maybe I need to build some courthouses and the Forbidden Palace.
A quick detour back to the northwest corner of the continent had Gandhi dead before his 5000th birthday (935AD).
Alex is next on my hit list. He has 7 cities on the mainland and 1 on an island. I still don't have macemen, and he has them, along with pikes and knights. But well-composed stacks of elephants and Xbows should neutralize his advantage. I start the war against him by killing a couple wandering knights, and beeline through Sparta and Athens (home of the Great Lighthouse). With these two cities safely in hand, Alex has no chance. Some musketmen start appearing near the end, but luckily elephants can be upgraded to Pinch without knowledge of Gunpowder in Vanilla. I make peace with Alex in 1160AD for Civil Service, and leave him a single island city. Now I can upgrade my few remaining axemen to maces and take on Hatty.
My scouting of Hatty shows 30 units in her 5 mega-cities. I see several musketmen, so I build some elephants in my Theocracy-aided cities so I can have Pinch protection. My two stacks of 20-25 units each sit north of Egypt, in two captured Greek cities that are completely swamped by Egyptian culture. I declare war on Hatty and back all of my units out of those two cities and let Hatty make the first move. She sends a few units to raze each city. Not what I was hoping for, but I kill the offending units and send my two stacks at two of her large cities. She's got a nice assortment of units that will make any of my units underdogs in a assault on the city. Well, that is until I hit them with 6-8 cats each. These two cities fall. She still has a few mini-stacks roaming around, but I've got the upper hand now.
I start working my way through the islands while fighting Hatty. Issy has three cities on a long island south of Timbuktu, plus two more somewhere. Still using galleys, I transfer about 10 units to that island and take the three cities. I find another single-tile island city that I take in an amphibious assault (amphibious elephants, yay!

). Her last city is at the very eastern end of the island chain, and Monty's three cities and Alex's one city stand between. So I make peace with her and go after Monty and Alex. I have Astro now, so galleons will make this go fast.
Alex is dead in 1286AD.
Monty is dead in 1292AD.
Hatty is dead in 1334AD.
Issy is dead in 1346AD.
I win a
Conquest victory in 1352AD for 195K points.
So it turns out I never really needed Astro (though it sped up the final island wars). The brave new world was chock-full-o-barbs in 1352AD, so there wasn't much room for easy settler spam. I should have just committed myself to all out Terra war and not worried about my economy going to crap.