Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.1030 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)

"Do you mean avoid "mixed cabin"?"

Exactly.

As to other matters ....

Asian carriers' Business Class is generally considered to be superior to U.S. carriers' BC, and to many European carriers' BC, as well.

Have you checked to see how many miles Aeroplan wants for NYC-BKK one-way in Business? If you do not need a stopover and if Aeroplan does not have a close-in award-booking fee like UA does, you might be able to save some $$$ by using Aeroplan for the outbound, and MileagePlus for the return (assuming that your return date is at least 21 days hence).