How can you expand that much while playing Ming? Do you keep the Temple faction at power all the time, or do you wait for others to declare war on you?
yep, the trick I use is to throw guarentees around like they are going out of fashion, sooner or later you'll get dragged into wars. The art is to lever every advantage out of every one. The problem is you run up infamy as you can rarely use BB efficient tools to take provinces. In my AAR, I'm up to the 1640s and have all of SE Asia (either owned or vassalised) and N India, as well as colonies in Australia and to Guam. In game I'm about 1780 and have a lot of the western side of N and C America.
After a while, I decided the Temple faction was actually the least useful, as if you really annoy someone like France they will feed you a nice regular stream of DOWs on you. Then you take revenge .
Overall Ming in 5.1 is perfectly playable & I think nicely balanced. Its powerful but constrained, and you tend to have batches of time where you just do one thing (so bureaucrats - catch up on your building; eunuchs - get colonising; Temple - beat up the neighbours).