When I first wrote about the SE I was under the belief that settling GSs was the way to go. Acidsatyr convinced me otherwise. The lightbulbed and traded-for beakers vastly outweigh the settled beakers in the short-to-mid-term, which is always more important than the long-and-very-long term in this game. Settling may be an attractive option if going for a space race win via SE, but I am still unsure about that.
re: Pyramids. People always say it's not necessary, and it isn't. BUT, it makes the SE incredibly more powerful (doubles all the base output of your specialists). So, if you have stone, go for it!! Also, this makes industrious leaders quite attractive for me. The best domination victory I've recorded thusfar was with Louis and I build the pyramids, GL, and parthenon and had a phenomenal economy, which I could completely transition into military production (draft/whipping) whenever I had a tech advantage, which I often had.
re: GL. It is never pyramids OR GL. The GL is the staple of the SE. You should always gun for it. You want to be generating GSs and two free scientists is just huge. Lit also comes with the NE (and the HE), which you should get going asap in your GL city (run many scientists to minimize the amount of GAs you get).
-re: Phil vs. Ind. These are two of the strongest SE traits. If you go phil, the goal is GSs early and often. So target the GL and get libraries up early to start producing them. If you go ind, the goal is the wonder combo: pyramids-parthenon (built in a military city to avoid GS-GE polution)-GL. Industrious will have better base beaker production. It will have slower and ultimately fewer GS production, but this is offset somewhat by the parthenon.
-Slavery vs Caste system: Again, it's not either-or, it's both, making spiritual an attractive SE trait. When you are in "research mode" you run caste system, along with pacificism and ideally representation (and mercantilism later). When you're in "military mode" you run slavery, along with feudalism or nationhood, theocracy, and ideally police state. The strength of the SE is the ability to transition your ENTIRE empire (minus say your HE city, which is constant) from research to military as dictated by the circumstances. You can see why I really like Rameses and Gandhi.
-Acidsatyr never had much use for CS (he liked its production bonus) and would never cottage the capital. The thing is the capital is usually high-food so makes a great SE city. It's really too bad there isn't a SE-economic civic in that category. I tend to cottage the capital and run bureaucracy until nationhood comes on board, but if the capital has amazing food output (specials, not floodplains) then I will pass on bureaucracy and run specialists instead.
Basically, the SE has two main economic functions: 1) beakers from scientists and 2) beakers from lightbulbing and trading lightbulbed techs. Originally, I failed to see the power of the latter and focused exclusively on the former. I think now that this is a mistake since you can use 'bulbed techs from GSs to beeline liberalism quite effectively, especially at higher levels.
The SE goes hand-in-hand with military pursuits since your base of farms everywhere allows you to regrow much faster after whipping and drafting. Also, since you are not relying on the science slider for beakers, you can expand your empire much larger, much earlier even to the point where your slider is at 0. And you can do this constantly throughout the game. This is in contrast to the CE where you want to stay over 50% and closer to 70%.