Never needed more than Rationalism in my domination games, to be honest. Culture has never been a concern.
While it is true that culture for culture's sake is a non issue in domination victories, I find myself purchasing social policies that stave off the inevitable unhappiness associated with a domination victory.
I've never pursued wars of aggression once my happiness dips below -20, so who knows? Maybe happiness really is a non issue in domination victories.
I don't know if it is programmed or luck, but later in the game city-states tend to have a longer leash when attacking. I've had a number of games where a surprise DoW ended up by having a city capped by an enemy city-state. In higher difficulties, city-states tend to have impressive armies.
I have the most miserable luck trying to get anti aircraft defenses to work for me in my games. Thus, I'm not a big fan of Civ V in the Atomic and Modern Ages.
Taken too literally. If your focus is pumping out military units, whatever city-states give you is likely not going to be of much use. Whenever I play a domination game I don't think "Gee, if I grab an alliance with that city-state, that should really give me an advantage! That extra pikeman alongside my riflemen popping every 4-5 turns will really boost my military might"
Actually, my thinking is "Gee, if I ally with that city-state, I will get free land units every 20 turns (or whatever), so I can concentrate on building the units that they can't provide! Ships, for example."
Again, taken too literally. If you are not purposely trying to game the system and sack each capital by T100, then you will eventually reach later techs. A domination victory is a domination victory; not really fair to say it isn't valid if you've reached bombers/battleships.
Like I said before, I am trying to sack each capital before air attacks become prevalent, but that isn't exactly "gaming" the system.
1. Civs will likely be pissed at you regardless, so sacking a city-state and taking the negative diplo hit isn't as big of a deal.
Well, perhaps we are going to have to distinguish between declaring war on a civilization and seizing one of their allied city states, and declaring war on a specific city state and seizing that city state.
Most of your arguments make sense for the former, but they don't make much sense for the latter.
Are we at least agreed that the latter situation is typically a foolish one, even when pursuing domination victories?