The Shun Dynasty was surprisingly well organized and was unafraid of using high tech weaponry (such as better cannon) but it would have had a hard time dealing with both the Manchus and what was left of the Ming Dynasty, especially since they have no navy to speak of.
Expect to see China split into two parts, at least for 20-30 years, as the Shun focus on issues related to food security and land distribution in the North China Plain. Then, they can get to the task of building enough of a navy to take on the Southern Ming.
If the Shun need to build a navy, the best place they can get one is from one of the Western powers. Probably the Dutch, although the Spanish are a possibility.
I think that the division of China would be an excellent opportunity for Western traders to break free of the Canton monopoly (or prevent it from occurring in the first place; aren't Westerners trading at all of the Southern Chinese ports at this point in time--the 1640s-1670s?). The Shun would likely want to trade with the West from Shandong, either from Qingdao or Weihawei on Shandong's eastern tip. Given time, Westerners could parlay that port into a permanent arrangement that would last even if and when China becomes reunified. And Westerners would still be able to trade at Canton.
And then there are the Manchus who haven't gone very far away. Just back to Manchuria. Which includes Lliaoning, which the Manchus are likely to be hanging onto for the forseeable future. And the Manchus are now likely to be expanding agriculture and their population in Manchuria. And permitting their own trade relations with the Western nations, probably at Andong, on the Yalu River, where this trade can unofficially tie into that of Korea's as well. This opens up another western port.
The Manchus will be facing other challenges. If they do not hang together, they may well be overwhelmed by the Dzungars, who are coalescing at this time. IOTL, with the resources of all of China behind them, the Chi'en Lung Emperor was finally able to annihilate the Dzungars in the 1750s after they had successfully resisted Q'ing control of Tibet and Western Mongolia for several generations by taking advantage of a succession squabble after the death of the Galdan Khan. ITTL, with the Shun defeating the Manchus, the Manchus may not be so lucky. The Dzungars may well unify the Mongols and if the Manchus do not hang together, the Dzungars may well conquer them and the Yakuts as well . See this "oldie but goodie" AH Dzungar wank for what they might have been capable of: Dzungaria, the Heartland empire
From: Byambaa Garid <bgarid@gse.mq.edu.au>
Date: 1997/06/25
Message-ID: <33B0F9A3.5B23@gse.mq.edu.au>
Newsgroups: soc.history.what-if