Note (only with 180 degree lie-flat bed seats):

1) Very couple friendly (middle seats, that is): OZ - could do on your outbound (select flights out of LAX and SFO)

2) Decent couple friendly seats: UA/CO (on 744 and select 772 flights), TK (only on their new 77W flights to LAX and some to JFK), LX on most of their flights to US/Canada

3) Great seat, but unreachable if you are redeeming miles with *A partner: SQ

And there are the 'older' generation business seats that are couple friendly as always on all other *A partners.

This information is not so difficult to find on your own with about 5 minutes of searching on the web.