I believe with the devaluation of avois points for long haul, you would be better crediting flights to AA since it sounds like you plan on redeeming for J long haul.
JFK-HKG on CX in J
Avois: 100,000 points
AAdvantage: 55,000 miles
Was there anything other than earn and burn you highly valued? Lounge access when traveling domestically, possibility of Op-ups, customer service, mileage upgrades (can't upgrade CX/JL with AA or BA)?