I've taken my weekened free time to start a game as France, 60% Continents Large, Monarch, and try to apply the strategies and lessons given here.
So far, in early age just built settlers, had two settler factories working, also built some workers and started manually improving everything. Got two luxuries, luckily iron and horses were nearby. Instead of building temples and libraries, or pop rushing, succesfully built the Colossus (which is a valuable early wonder) in my capital for the commerce, then started building masses of Swordsmen in anticipation of war.
Was still in Despo, found the Zulu, dowed the Zulu, mostly well behind in culture and infra. Swordsmen rush killed most of them, sent settlers to remaining empty spaces. Switched capital earliest of all to build infra, started building temples to get border pops on my cities, by then I had lots of land including one island-like space (but still connected thru two chokepoints) that was all mine.
Used the luxury slider up to 30 and 40% just like people said. WW was somewhat hitting me, but luxuries stopped it. Then started trading for luxuries, building stuff, lowered it to 10% without detriment to me.
Also switched as early as possible to Republic, and this time, got it working.
What I know now is by building only the essentials and adopting the new Civfanatics inspired grand strategy, I was able to keep Republic working from early on. I beelined to it, and switched at about 250BC.
Previously, my strategy worked around hitting critical mass, using pop rush to build culture and units, and then switching out of Monarchy and Despo only after critical mass was hit, I was already big, and we would be a bit late, like 800 or 1000 AD.
Now however I'm consistently capable of keeping Republic working from much earlier, thru the war and critical expansion phase, even before I hit critical mass. And the technological and economic boni of Republic are just too large to miss, so now I finally learned to use it consistently.