Deng Xiaoping also introduced the limited term to ensure the focus was on the party and country rather than the leader. Or words to that effect. And look what's Xi has done.
Its unlikely they have invested all that money in South China Sea to not reap a reward. That said they are (probably) too smart to provoke war. They may just pick their time to deepen their interests there....perhaps now while US and UK are weak and Aus still relies on China to buy its rather limited range of exports. Taiwan is indeed an interesting beast though, they have serious weaponry (unlike HK).