That depends a lot on whether you are sitting in one of the center AA rear facing seats between high sides too narrow to fit arms by your side if you have broad (i.e., adult male) shoulders, or one of the other seats that is actually comfortable. On a close-in booking, all the good seats will have been taken already as they are not held back for status passengers on close in bookings like on BA. Sure, the wifi on AA is a win, but BA's CW actually has enough room for arms and shoulders in all seats.

BA's cabin is actually dark and fairly quiet on an overnight flight because there are opaque, heavy curtains. AA's is lit by the galley floodlighting and the galley sound is not muted by any effective curtain.

The timing is the biggest win here: the daytime flight is far better for avoiding jetlag and a short night sleep. Just don't sit in the rear facing center seats.