A China which is more open to trade and foreign exchanges would probably lengthen the lifespan of the Ming Dynasty, yet no Chinese dynasty (at least since the Qin) has lasted that long. It seems inevitable that even the most successful and prosperous dynasty will fall to corruption and decadence in some form. What might change is how the Ming falls, and what replaces it. Would disgruntled eunuchs stage a coup against an ineffective emperor, or would a peasant lead a rebellion as in OTL? Would northern invaders step into the vacuum at the right time as the Manchus did OTL? Or does China enter a "Three Kingdoms" or "Five Dynasties and Ten Kingdoms", or north-south-split period?
One thing's for sure: whatever succeeds the Ming will be much more open and focused on reform than the OTL Qing.