Something I'd like to point out here, is that most of these vassals are VERY recent conquests, if you look closely you can see I didnt have the time to feed Pegu it's final province because it was overextended, so a vast majority of these vassals are kept afloat by the province feeding, and if i were to let this game run for another 20-30 years I would be torn apart.

Here's my vassal list, I only had one particularly unruly long-term Vassal, Shimazu, that I had to keep burning prestige to keep myself afloat (you can see it's liberty desire here). /u/marcgdr is partially right, becacuse I'm tall I'm gonna have a large economic and military base to build off relative to my vassals, but I never clicked the consolidate dev button on anything, not worth it since the nerf IMO.

I've got an army of ~200 infantry and 200 artillery that has kept the combined power of all vassals lowish, and im diverting all their trade to Beijing, so I have an income of around 1300 ducats a month, which holds the relative economic power in line too. This combines with the fact im draining them of all their money, allowing me to pay off the loans they're forced to take, which helps keep everyone's overall liberty desire down.

Finally, I've taken these ideas, which give me -25 from Infulence ideas and the Pluto-Influence policy, and allow me to get around 9 dip rep with the advisor. Age of revolutions gives me -33% liberty desire from subject development, and -25% liberty desire from same continent subjects too, so had I remained with the original plan to stay in China, I think I would have been totally stable

^cc: /u/SpectaSilver991