I think it was lizyu who said J-16 would fill a role similar to F-15E, and it would be based on the Flanker line. However, huzhigeng is contradicting him by saying J-16 would not be some Su-30 offshoot . There's some major confusion going on. The only thing that can be confirmed is SAC is developing a new plane with conventional layout, CARET inlet with multirole focus. It would not be quite as capable as J-20 in A2A role. It's not known what the designation will be, but it might be J-16.
"pupu: 苏-30MKK2跟歼-16相比的差距可就大了去了,几乎差了将近半代有余……"
J-20 is designed to be long and slender to reduce drag for supercruise. Larger body allows it to carry more fuel and supercruise for longer, not to mention increased combat radius. PLAAF predicted that future air combat will depend more on supersonic maneovures instead of subsonic manoevures. The design obviously is geared towards such.