From 2360, we cancel Archery and research The Wheel (I think you did this anyway), then AH. We immediately revolt to slavery. If events are off, you probably want to revolt to slavery as soon as BW is done, unless you're building a worker or settler or something. With events on, you run the risk of the annoying slave rebellion, but you still don't want to wait too long. We set up roads to Hamburg probably much like you did, and settle Munich in the same spot (though we can see the horses now).
I agree that taking out Joao is definitely the move here. You really only have room to expand south, and the land isn't that great. You could get some decent food and production, but you have no rivers so commerce would be a problem. You could run a SE but it seems much easier to just take Joao's juicy flood plains.
Since we have horses, I prefer to HA rush here. I'm perhaps a bit more partial to HA rushes than I should be but I really prefer the mobility. So we go Writing > Alphabet after AH. Actually I think I got mysticism first; some of our cities don't really need libraries now but they do need border pops. Anyway, we get a library up ASAP in Berlin and begin running two scientists. Our chops are limited; we only chop things we need quickly, like libraries. We get our barracks up while we go for Alphabet. We'll save as many chops as possible for granaries/stables/HAs. Note we could get away with going pottery first before writing; the benefit is quicker granaries and a discount on writing, but we'd get our libraries and GS later, and it would take longer to get to alphabet (where we can just trade for pottery). I'd probably go pottery first here if we had something worthwhile to cottage (we do not).
You pretty much need to go alphabet at this level because the AIs simply take too long to get it themselves. We need to trade for archery, pottery, and iron working. Archery we need to build HAs, pottery for granaries, and IW isn't necessary, but it lets us know if and where our opponent has metal for spears. We find that no one even has writing yet, which is sort of a problem because the AI won't trade IW for writing (we need to trade Alphabet), so we just make sure the AI who will give us IW (Cathy) gets writing for us in our trades.
We find Iron west of Munich. We could (should, probably) settle it so Joao won't have any metal, but I'm lazy and just keep going with my 3 cities. Joao probably won't settle it in time, and if he does, it's right next to our borders and easy to pillage immediately.
We go HBR after Alphabet obviously, with everyone building research (we've finished our barracks/granaries by now). Our GS will bulb math when he's done for the increased yield from chops and discount on currency; our workers start but do not finish their chops (left at 1 turn) until we can get Math. Our GS pops about the same time we finish HBR, and we put our chops through for quick stables, then switch to HAs. We'll need currency and CoL next to support our soon to be much larger empire.
We 2 pop whip to get HAs out quickly. If you don't use whipping much, basically the idea is that 1 pop gives 90 hammers on marathon, and HAs cost 100 hammers, so you change your citizens so that you get 9 or fewer hammers right as you start a new HA, then whip for 2 pop next turn. With the granary, you should almost immediately grow back to 3 pop (or 4 in your capital), and you'll also have most of a 2nd HA done. Doing this, we get a reasonable sized HA army out quickly.
Joao has just settled the iron and is building a road on the iron. Too late for him unfortunately. We declare on him and use an old chariot to capture the worker and pillage the road. Meanwhile our HAs go about taking his other cities. He's built walls in some of his cities, which is annoying, but doesn't matter really without spears.
By 850 BC, he only has his 'iron' city left:
I'm lazy, so I'm just going to sit there until it hits pop 2 so I don't raze it. Meanwhile, the immediate goal is to get to Currency ASAP, and work on improving Joao's rather under-developed land (though he left us plenty of forest). This is somewhat annoying since we have practically no commerce from our original cities, so we switch to research to get to currency quickly, where we'll get bonus commerce for another trade route, and can build wealth, which is stronger than research. Not like we need more HAs anyway.
In 780 BC, his iron city finally grows to 2 so we can take it.
If we had a stronger commerce base, we could easily take out Cathy too, but our economy is pretty weak now. We also have a lot of land up north to spawn bust; likely will need 4-5 units to do so. We probably could still do it but it's not really necessary; we already have enough cities and available sites to easily outpace the AI.
We have two (somewhat related) major concerns as we recover our economy: Still no religion on this continent, and we currently have no way of increasing our happiness cap. The immediate solution is to settle the silver to the north and the gems to the south ASAP. If we're lucky, we'll found confucianism as we are going CoL next. In the mean time, clearing all the forests around Joao's cities helps us quickly get up necessary infrastructure there. Lisbon is cottaged heavily and will be our bureaucracy capital/oxford site; Berlin will be our GP farm.
Confucianism is founded in a far away land 3 turns before we get to CoL, so we have to go to plan B: bulbing Philosophy. We go Aesthetics > Literature next and will go for TGLibrary and National Epic in Berlin. In the meantime, we run wealth in every city that doesn't have anything meaningful to build anymore and keep our science slider as high as we can.
Sury and Cathy are teching terribly slow and completely unreliable as tech trade partners; we consider ourselves lucky when we can finally get even poly/meditation from them. The good news is that most likely the tech rate on the other continent isn't particularly fast either; since they've now founded 4 religions, and likely will get Christianity too, they're probably not the most peaceful ever, although it probably won't matter even if they are; we should be able to outpace the AI on this level with this many cities.
We backfill the dye/fish to the southeast and the pig/corn to the north. I don't see the need to settle the ice/crab or even the sheep by Berlin. Plains/Sheep is a weak tile.
Anyway, we get TGLib in Berlin and soon after bulb Philosophy. Our continent finally has a religion! Without any other possible religions, it'll auto-spread to everyone pretty much. A shrine would be pretty profitable here, but isn't necessary. I'd probably go Angkor Wat and get it if we had stone; it's probably not a bad idea to do it anyway, but I choose to just run 1 priest in Berlin and hope we get lucky. At least that way we know we won't get deluged with unnecessary extra prophets.
We go Music next for the GA (usually very easy to win on Prince) so we can get a golden age and switch civics. We'll wait until we can get CS during out golden age before we pop it, then switch into Organized Religion/Hereditary Rule (we went Monarchy after Music) and Taoism immediately, then try not to forget to switch into Bureaucracy before the golden age ends, and build a palace in Lisbon.
Backstabbing Cathy declares on us at some point (we beg for peace when she first starts plotting, but she declares on us after it ends) but her stack is really unimpressive. She even bribes Sury in on us, but whatever, he's too far away to matter. We could take Cathy out pretty easily now, but I'd rather build the tech lead and take whatever wonders I feel necessary. Anyway, once Taoism spreads out more we'll all be pretty buddy-buddy with each other.
It's pretty straightforward from here: next GS goes academy in Lisbon, next bulbs education. I stopped around here; any number of options is open here for victory. We could get curiaseers pretty soon if we wanted, or we could continue teching and get cavalry, or we could just play peaceful. In any case, we can take our continent if we want, and barring something super crazy weird going on in the other continent, we'll be too big and advanced for a likely divided continent to contend with.
Here we are in 725 AD... building a bunch of colosseums because we got the sports league event, so we built Statue of Zeus and will take a silly golden age (Cathy traded us Ivory). We'll probably throw workshops on the grassland to the east and run state property eventually. Cathy looks like she's going to be worthless as a tech partner, but at least Sury should get us a tech here and there. Anyway, the game is pretty much won here, though I'll probably play it out at some point.
I'm just showing how I've done it; but I believe first-hand experience is the best way to learn, so I suggest you go on with your own game and if you like some of the things I've done, feel free to try them 
I'll try continue from my save and post the results later 
I suggest aiming for long-term goals now; obviously, you may want to kill Joao, then aim for whatever victory condition you want and never straying. Look for wonders and techs you need (not want 
) and/or befriend him (again, for the time being 
.) Next step is to amass a fleet of galleons and overload it with cuirs/rifles/cannon/cav/whatever. Also, earlier on, I picked up Christianity (was beaten to Philo, but ah well 
