Thanks for the compliment!
The empire was indeed huge, it was starting to be pretty annoying to micro even at the crude level. I did play SP on huge marathon so I'm used to big empires but this was pretty big even compared to those.
I don't think Rusten really needed to get naval tech faster, but he definitely should have (as he himself said) built more iron clads (we were prepared to face those in big numbers and had huge amount of ships+ airships that would have helped a lot, but we would not have complete naval dominance that we had now). Even with infantry it gets hard to defend vs commando cav (that we were building at around rate of 4 in 5 turns) if you don't have any vision on which ports we threathen etc (he would have got airships of his own soonish though).
Going for physics vs AL is not that much infantry vs airships but factories vs everything else. We went airships first as we got GS that secured us 4man GA early (that we would have started next turn), as airships really help a lot in this kind of war where we are not planning to fight stack vs stack but hit where enemy is weak and burn stuff, and as we really needed communism Gspy for GA purposes so we were going to that direction in any case. In general I usually prefer going for assembly line for factories first (and if you get good window to attack with infantry that's also great, but cannons+ experienced cav are not completely horrible in fight vs infantry).
For the most important trait: First of all you need lots of skill. You should have at least resonable micro skills not to be left behind in first 80 turns. Then you need skill to plan for right tech path and for the correct macro decisions. And you need to eat someone at some point (probably multiple times), so you need to have at least resonable sense of warfare. But the fact that you need skill to be good at something is pretty given.
What is sometime overlooked is that you need endurance. The game is long and you have to keep making right decisions for a long time to improve your position. Also things will keep going sideways and you have to bounce back (in pb42 it would have been easy to give up after we scouted our start and compared to what Krill etc had, or after Krill attacked us with knights and we were sure that we are both going down. Or in this gameafter we lost city to barb with around 2% odds etc). And in later stages of the game the turns can be pretty long
![smile smile](https://www.realmsbeyond.net/forums/images/smilies/smile2.gif)
. I'm pretty competetive person and I like to win, so that's where the endurance comes for me.
As for AI best resembling our play style I'm honestly not sure ( I have played K-mod for really long time and it changes AI behavious quite a lot). But it would be balanced/opportunistic type of leader who wants to eat enemy civs in cost effecient manner after getting the necessary lead for that through fast expansion and good micro.