I'd think carefully about an AONEx as A seems a threatened species on many carriers. D is a certainty.
L will be problematic for last minute changes as it sells out quickly. D may be best for a flexible set of dates (but YMMV).
LHR-LAX will be on BA. Can you earn AA points on this sector?
DFW-ANC is summer seasonal (forget about winter). Even in AA F on the 757, this is not a pleasant experience for 7 hrs.
JFK-HKG will be on CX. Even on the AA code-share, can you use AA points to upgrade if you choose L class? I don't know whether you can use AA points to upgrade on CX.
Move quickly as I suspect the cheap origin countries have good business. Make sure you are aware of the rules for changing the first sector.