USA had the GW, and I ended up razing 2-3 USA cities and one Poly city. Taking Washington was tough with all the hills and his Minutemen upgraded to Rifles. I ended up with 7 Arty and they have been mostly used to kill units. Getting ready to seige Iroq cap - I screwed up taking his newer coastal city instead of the more developed inland one. This put me in Frigate range and also the city sucks! While trying to force my way towards his cap, I ended up with Cav super-exposed, so I just blasted the inland city and took it. It feels like I've had many screw-ups like that this game. Had one good stroke of luck - I made peace with USA to divert towards Poly, but my spy stayed in Washington, and one turn before it's capture I stole Rifling.
After beelining Arty I nabbed ST (this game will go forever) and started going for Flight/Prora, then will go waaaay back to Optics and top tier towards oil. Poc is a beast, but still giving me decent trades.
I was going to whack through USA and take Cusco, but Iroq DOW'd me and I decided the path to Cusco was much easier from Iroq lands. I may split my forces, one army S for Cusco, and one E to liberate Pedro and get his cap, all in Poc's hands. I assume he may have Flight by then, hard to tell. I am going to end up leaving Iroq with one city, it seems.
One other option would be to tech up and go for BBs - way too late to Friagte rush Poc's cap, I assume. Monte still seems formidable, big army and not so happy. In retrospect I should have killed one of his last 3 cities.
Besides all the themes/NWs and stuff, horsies have been very hard to come by (and the map has almost no coal). I screwed up and upgraded too many Landsknechts, so purposefully suicided some Lancers to get more Cav.