Counting on Chinese stupidity is like counting on the sunrise at dawn.
From my humble observations, the PRC is pursuing a strategy of salami slicing. They will push where ever there is room and they will yield wherever there is push back. They won't do anything drastic as long as the push back against them isn't drastic. And even assuming drastic action against China, such as the complete destruction of the PLA Navy in the South China Sea and Hainan areas, the PRC can't really do anything drastic yet anyway. They are still mostly in the waiting phase. Their patience has been demonstrated in the 2014 umbrella protests in Hong Kong. So in the meantime, they will continue their economic development. They are currently at an economic transition that is difficult to pull off and it may test the very limits of the CCP's interest in its own existence as the sole political party with very tight control on speech and its necessity to conduct "anti-corruption" campaigns for the purpose of eliminating political opposition within the CCP. That economic transition will be increasing domestic consumption, relying less on exports, and develop a vibrant high tech industry and a multitude of other briskly functioning industries so that they all augment each other. By the very nature of the CCP, a healthy environment for such changes may not be possible.
So while they do a lot of stupid stuff internally that ultimately shoots them in the foot for becoming the regional power in Asia and the Asia-pacific with generally favorable opinions among its neighbors. A new counter weight to American stupidity would be nice. The PRC's strategy is to try to become the regional power while ensuring CCP rule. Their foreign policy so far makes that clear while also serving, as duel purpose, domestic consumption for rally around the effects for CCP. That totally ruins China's chance to become a favorable regional power, which is highly unfortunate but not so surprising giving their long track record, but it still does not change their aspiration to become the regional power as they politically currently are. So they won't do anything drastic. The construction of 3 airstrips on man-made islands in the South China Sea might have been too drastic, and thus be what you have been praying for, as now many neighboring countries are losing trust in China. Their 9 dash line claim is too big also. A funny joke 10 years ago. But since then, future prospects take the joke element away.
However, China did gain influence in a few neighboring countries in exchange for the many that lost trust in China, namely South Korea, Thailand, Cambodia, and possibly Myanmar. But these countries generally play middle power, taking advantage of the tuck and pull between China on one hand and the US/Japan on the other. South Korea is particularly tied to China because of China holds the greatest external hand on North Korea. And it guarantees South Korea large markets. It may be a good long term strategy for South Korea, but in the short and medium term, lets just say, the Koreatimes news webpage tends to get under my skin almost every time I visit it and will continue to do so. Well in short, those 4 probably won't go past the middle stance between China and the US/Japan. But it definitely demands great attention with long term prospects in mind, keeping a close eye to see if they do pass the middle stance and shift towards China. And this must be considered should the West get into a new crusade in a end of the world scenario in the ME and North Africa as that will drain the treasure of the west, enabling a good opportunity for the PRC to greatly raise its relative power in the world since they will just stand by and watch the west and Islam whack each other.