I also thought about which issue is more important AP points versus no forex fees - if used in the U.S. (vs international)

I have both AMEX Gold Rewards (Canadian) and a no-fee USD MC. Obviously anything spent on the AX will be 1:1 transferable to Aeroplan and Avios.

The US MC makes a huge difference as I am charged in USD and pay in USD. For certain purchases, I have accepted that I will sacrifice earning points for the ability not to have to pay USexchange.

You just need to decide what is more important based on your spending habits.