I'm pretty sure some kind of two seat J-15S for training pilots is needed. The PLAAF will get tired of having their trained pilots sucked out of them to serve on the carrier.
As far as i know the Naval Aviation trains their own pilots already since some yeras, they are no longer former PLAAF pilots.
To admit IMO the Chinese navy most of all needs a decent carrier-capable trainer and I expect not the JL-9 but a development of the JL-10 (hopefully in the not too far future). Otherwise I expect the transition will take place from this JL-10G to J-15 and only then from the J-15 to the J-15D, so that most likely experienced J-15 pilots will fly the J-15D first and as such not really a dedicated trainer is needed.
Just my 2 cents.
Deino