While we are speculating about new carriers, the Chinese hardly uses their existing carrier. Something is wrong.
What kind and number of aircraft are using the carrier? More than the three J-15?
While many people would like to see China launch and catch extremely large number of aircraft in all condition all the time, the fact still remains that China is new to using aircraft carrier and carrier's operation. As much as we would all like to see the Chinese being extremely good at these operations, it is not possible currently.
The US, UK, France, Russia and even the Indians have decades of experience with the carrier... with the US more like evolution in the carrier operation, coming right from WW2, to cold war, to modern era, etc. Carrier operation is like a second nature of the US...
China is just beginning. They send their carrier out, launch a couple of aircraft, then come back and review what was done correctly and what is not, and how to improve. Then they improvise their operation procedure, etc, and send their ship out again. This process go on and on, until they more or less perfect the SOP. At present, I think, the aircraft launching and the such was already tested, the J-15 performed well and to the satisfaction of the PLA, but although launching aircraft and capturing them back safely is among the most important thing of aircraft carrier operation, there are other things that needed to be addressed too. The Chinese might be refining all those operation now.
Also, I have this feeling that we will not be seeing another aircraft carrier until the PLA perfected their SOP or near to perfecting their SOP.