ElWanderer
Warlord
Secondly, I should have started signing RA's much earlier because I have only recently got to navigation and got some SoL's out there.
Generally I'd agree with you - in the last immortal domination TSG, it was a succession of research agreements that kept me marginally ahead tech-wise for most of the game (and therefore able to stomp the AI with better units). However, in this game I got navigation on T172 without any research agreements. I got there by avoiding the bottom half of the research except for iron working (I didn't have roads for ages!) and bulbing Astronomy and Navigation with great scientists from the Great Library and Porcelain Tower (I also got a university up for specialists, but that was late on and only shaved a turn or two off). On easier difficulty levels, I like to build both the Great Library and the Oracle, for getting a great scientist out faster, but that wasn't an option here.
Thirdly, I need to be more aggressive in the early stages - that's just not my style of play because I am more comfortable with science or culture victories.
Me too, I'm quite happy to smite whoever attacks me, but early aggression isn't usually my style.
T262 update: I lost a unit

My highly promoted longswordsman got run over by a caravel belonging to a City State allied to Rome - I've still no idea where it came from. Fortunately, I had another or that could have been an embarrassing end to the invasion! I dread to think what my kill ratio is; it's been like whack-a-mole at times.
Both Siam and Songhai's capitals fell fairly easily and they're giving me gpt for peace. I have just captured Rome (which at combat strength 55, was only taking one damage from each shot) but not killed enough Romans to get a peace deal yet. Caesar was top of the scoreboard and slightly ahead of me in tech (he has cannons, cavalry and frigates). Helpfully, he had built the Great Lighthouse and Forbidden Palace in Rome, so those are now mine.
Next up will probably be Egypt (who still have a mad carpet of war chariots), then China or Greece. I have research agreements with Japan, France and Persia, so I'm leaving those until last. That must be six capitals down, six to go. At the rate of a capture every 10 turns or so, I guess that's a rough predicted finish time of T325.
Possible spoilers regarding bits of the map around Siam and France:
Spoiler :
- Heh, didn't expect to see El Dorado. Was tempted to wrest it off Siam, but he made me a peace offer I felt I ought to accept so I could move on to the next civ.
- Hmmm, Paris seems to be located in a more awkward spot to get to than the other capitals. May have to capture a city to the north of it, then emplace artillery to beef up the bombardment.
- When I gave one of my ships of the line the Supply [heal 2HP outside friendly territory] promotion, it gained an extra movement point. That doesn't seem to be listed as an effect... is this expected?
- Halfway through my play session last night (I think the game was running for about five hours, though I didn't play solidly), my ships lost the ability to run-over embarked units. Instead they were able to one-shot them with bombardments. A few turns later, they were back to normal. Has anyone else had that happen?