The Japanese were pretty well ensconced in Manchuria. They could probably have held it pretty much indefinitely. Yes, it would have meant continuous tension with China, and perhaps it would be better not to. However, the area is rich in coal and other resources, and it might well be tough for Japan to do as well as OTL without them.
However, the Kwantung army absolutely positively has to be reigned in. Without them, the huge weeping sore of the Chinese invasion could be prevented, and America kept from being hostile, etc.
Given more time, Taiwan may well end up Japanese (i.e. viewed essentially as another Home Island), that would bump up Japanese power.
If Japan took Taiwan from the Dutch before the Chinese got really going there, Taiwan would now be as Japanese as, say, Okinawa.
Taking the Philippines might be possible, might be a step too far. Certainly it'd be tough to Nipponize them.
Treating Korea better, so Korea actually accepted Japanese rule would help. Don't know if there's any plausible PoD there...