Our spiritual father Confucius taught us to value peace over conflict, accommodation rather than confrontation. This kind of inward-looking, self-reliant, pacifistic culture is imprinted in our genes. I don't think China will become an aggressive power when it grows strong.
Look at interest too, China is now the number one trader with more than 130 countries in the world. If you can get what you want through trade, why bother sending gumptions and airplanes. China has already clearly defined its territorial claims, that is the Chinese mainland and the surrounding seas plus Taiwan, no more and no less.