So ... having played a couple dozen games at Monarch, and won about half of them, I think I'm ready to go up a notch to Emperor. Any particular tips? I've read the "Monarch to Emperor" article in the War Academy, but was wondering what other ideas some might come up with that aren't in that (or another) article.
The step from monarch to emperor is a mild one. So there is little need for particulars.
I often find a game on a lower difficulty but with a load of sub-optimum settings can provide a similar level of challenge but a bit more variety and unpredictability.
Indeed. Personally i prefer good starting conditions at higher settings, but i fully agree with your point.
What tjs282 said is right. No happiness, no empire. Hook up luxuries as soon as possible to keep your cities happy and productive. If your map doesn't have a close lux, or iron you can use, consider abandoning it and starting over.
In my opinion neither near luxuries nor close iron are essential. Getting them somehow somewhen is helpful, but doing so by trade is perfectly acceptable in the mid run.
What is essential is starting at a river. This enables city size which is essential once you are republic and the extra commerce from rivers is essential for a good chance at the republic slingshot.
Also, to avoid unfortunate declarations of war, just give the AI what they want.
True. It may take getting used to that, but it often is the wiser course of action.
Don't hook up extra luxes unless you are ready to trade - you could get a demand for horse or gems and you get declared on by a superior civ and lose a bunch of cities.
This may or may not be helpful, but in my opinion it is not essential. Accepting demands is a good way of getting on the good side of AI.
You HAVE to tech trade aggressively
That is essential.
, pick techs the AI doesn't prefer and ride that Industrial era tech boost from the AI's being obsessesed with Communism, Fascism and Espionage while you get ToE and speed ahead.
This can be helpful at times. Most of the time it is no big worry, though. The mentioned period of the (early) industrial age is important, but also obvious. But then again many thing are obvious after you have understood them.
Also, remember that war is almost mandatory at higher levels. Your true advantage as a human over the AI is that they can't run a war at all. Built cats/trebs/artillery in huge stacks and the AI cities will fall, giving you all the tech and gold you need and taking out their ability to out tech and out build you. If you aren't the bully on your continent, you will be bullied.
Artillery can be helpful, but large numbers of them may not be the best course of action. Not using artillery or only in small numbers that donnot slow down your advance can be good alternative, if you create military alliances and simply use fast units like cavalry to annex an enemy fast after friendly AIs take the brunt of the initial assault.
If however you are faced with a presumably long war of attrition, then artillery becomes somewhat essential as the kill ratio tends to become more important than skimping on unit support. That is until you have won the attrition and are at risk of increasing the size of your military beyond reason. That may seem like an unlikely problem, but it can become relevant. Finding the right balance can be tricky.