I'd wait, personally, if you're looking for a horse to carry you for a long stretch. IMO, it's likely AA will bring about some significant changes to its FFP, and it's not at all clear where this airline is going.

The Legacy AA fleet has Main Cabin Extra (an economy section with more leg room), yet no mention has been made about MCE being added to the US fleet (are they considering deleting it from the AA fleet?). AA is adding new "no frills" fares; lower priced fares may earn fractional miles and / or status credit - we don't know yet. There are changes that have been rumored to the FFP - what they might be, we don't know yet. AA FAs and Pilots have contracts, but full integration is still some time away; employee morale doesn't seem good. Mechanics are agitating for a contract - there's evidence they're causing delays by such shenanigans as delaying maintenance call response, "sequestering" maintenance logs for an hour or more when maintenance is completed and further inconveniencing passengers. Etc.