I quite like the idea of the Air Force and land based naval aviation eventually both purchasing a number of KJ-600s as well to supplement their main AEW&C fleet, both for the conventional AEW&C role, but also to integrate KJ-600s with ground based air defence systems in a more direct tactical manner to provide long range OTH CeC capability, especially against low flying targets like cruise missiles, which obviously ground based radar alone would be unable to adequately provide that sort of coverage for.
In the long term of course such a role would be best fulfilled by some kind of long endurance unmanned platform whether it be a tethered high altitude radar equipped aerostat or some kind of AEW UAV, but such an effort would likely need many years to have the physical platforms themselves reach maturity let alone the onboard sensors, and datalinks to control them.
OTOH, something like KJ-600 would be a much more conventional and directly applicable solution in supporting ground based IADS, while of course also being available to take part in the kind of high demand, low density role of AEW&C and supplementing the larger and longer range KJ-2000/200/500 etc platforms, especially as all AEW&C platforms will likely be high value targets that the enemy will want to take out and so a degree of attrition during wartime will have to be expected and should try to be compensated for during peacetime.