Why go for BA Gold?
 

Currently NYC based and future work will take me more over the Pacific than TATL so my actual BA flying will be reduced. I don't do much US domestic.

I'm currently about 300 TP away from BA Gold which I'd be able to reach with my next two or three trips. So not really knowing the benifits of Gold I looked them up and was surprised that the isn't any mileage tier bonus over Silver.

So is it worth me continuing to build in BA or should I switch to AA now? I'm using miles for redemptions on CX/JL in J or, only if I have to, use AA for ug's from Y.

Would AA do a status match?

Thanks

Can't answer the rest but AA will do a Platinum challenge that will get you to Plat fairly quickly (depending on the class you fly, one or two flights to Asia should get you there). See here or the AA thread on Gold and Plat challenges. If you have booked travel they may give you Gold when you sign up.

I believe with the devaluation of avois points for long haul, you would be better crediting flights to AA since it sounds like you plan on redeeming for J long haul.

JFK-HKG on CX in J
Avois: 100,000 points
AAdvantage: 55,000 miles

Was there anything other than earn and burn you highly valued? Lounge access when traveling domestically, possibility of Op-ups, customer service, mileage upgrades (can't upgrade CX/JL with AA or BA)?

Not really tbh, the MFU on BA is nice when I can get it, but clearly now the advantage of the lower redemption rates using AA miles is going to win over for me.

Oh, go for BA Gold first, then do the Platinum challenge on AA. Since you said more TPAC than TATL, the Gold card might be advantageous for the TATL legs