Personally, I would keep the BA Gold. It is easy to maintain if you do premium travel and also gives access to AA Flagship/Admirals Club lounges even when travelling domestically in the US. The main benefit that the AA scheme would give you would be the ability to upgrade on domestic services which you could do with Gold / platinum status on AA. On your OW 1st ticket, you should be able to retain Gold with BA plus get 6667 miles of flights to credit to AA and get Platinum via their challenge.

Dave