So winning without war is a bit more tricky than just beating everyone up, and 4 cities is a bit tight, could dowith a 5th one really. On the plus side Poland is pretty good for this as we need enough polices to build later wonders, and Poland makes than super easy.
At this point I'm already getting to the end game, where it is only other building some buildings that provide large benefits. Any science or production ones but otherwise I tend to just do science conversion. Which makes Wind plants one of the most important.
On the plus side everyone really loves me. Lots of trying to avoid upsetting anyone has helped but it is a bit random. This lets me propose things everyone likes to get even more loved. Siam even offers me a defensive pact, which doesn't make much sense but I'll certainly take it and a bit of money.
There is a pretty long stretch for very little happening, where I pull further and further ahead. You do need ot be rather ahead because the last age bonuses are huge and the AI will catch up. Siam seems to really fall off here, getting behind Greece and never catching up. I don't really know why Greece is strongest but they are my only really competition from here on.
This made no difference but I didn't know CS could give you such high tech units. I guess you need the resource.
So the edge a human has over the AI is lining things up better and planning in general. You can't produce as much science or production, but you can spend it better. I went right for Hubble as that is the important wonder, you really do't want them getting it. apollo first is nice but hard to do if you are lose together. I delayed the 2 free techs off order as long as possible so I could take two expensive techs near the end of the tree. I don't think Cern really does anything as you need too many techs to build it and you will be close to the end of the tech tree before you can start it. At which point you want to be building spaceship parts. You need to take the bottom tech not right at the end as it gives 3 parts, the other three are pretty much identical. I started building 4 parts all at once and once my capital finished one I had the tech for the next so I could start building that. It is pretty hard to line everything up perfectly, and the AI's spy killed my last GS so it didn't line up exactly anyway. I had 5 GE saved up and used them to finish the last two parts. I took all five to finish a part so i spread them out so both finished on the same turn. Greece kept up with me on tech but only finished one part before I won. Siam had a bunch of tourism but wasn't that close to getting influential on everyone. They had also passed united nations but were a good 10 votes short. I don't think the AI will ever win a non-science victory first unless it really messes something up.
Overall this was a pretty normal win. Poland's ability is good lets you focus a bit less on culture, but I did end up with 3 extra polices that did very little. My spys were awful and just kept getting killed, which was a real pain and problem slowed down the win a bit.