Thanks for the extensive reply. I think I'm not alone in the standard map preference (IIRC, Walter said he plays standard maps), but I know I'm definitely in the minority among regular posters here. The thing is, though, that the global modifier as it was literally broke the game on that setting, so I don't think my suggestion was out of place. It's likely that you're a stronger player than me (I'm starting to get comfortable on Monarch with raging barbs) and are better at managing it in general, but in the long post where I mentioned that, I hadn't even conquered so extensively, nor lost more than perhaps a third of the stack I was using in an overseas invasion, and my global modifier skyrocketed to well over 200% if I remember correctly, which is beyond the pale of anything you can realistically do as the player to control it. It was also redundant because excess unhappiness from war weariness is already a significant source of separatism, but that one actually has bearing on your local stability via varying levels of happiness. I am almost positive that this is the reason why the feature was considered broken and removed from the game, for the AI and the player.
The biggest variable here does seem to be the map size though, since the war weariness quotient does scale directly with map size, while I'm not sure that the revolution mechanic recognizes this and adjusts accordingly. Still, though, I get positive separatism issues and see actual revolutions in my games almost every time (and the "you're leading the score" global modifier is also really hard to deal with, since AFAIK it's a direct ratio with your percentage of score lead, so that if you're ahead by 25%, you now have that applied to every city in addition to anything else, which is a lot), so I don't think it was overcorrected. It's just that it doesn't break the feasibility of conquest completely. I'm probably a 6/10 on the warmongering preference scale - I prefer expand aggressively in the early game via peaceful settlement, then build up domestically until relatively late in the game, if I decided to go for domination. Generally, I only wage occasional opportunistic wars unless they are meant to be a home stretch to winning the game, but it's very annoying when even doing that results in unavoidable collapse of your empire. Either way, long and short, I think it's the map size making the enormous difference here between our experiences.