My advice is not to use Malev in your trip due to their problematic reliability. Flight cancellations are far more frequent with them due to their very small fleet. I would not take such risk, especially in colder months when weather-related irregular operations are far more frequent. Spring (the off-peak season for the coach award) is still very cold in that part of the world.

I would use BA as much as possible for your intra europe travel, and may use them for the transatlantic portion from Toronto.

From my memory, there is a Lan 747 flight between JFK & YYZ that you can also look at, other than the small planes AA flies between New York and Toronto.

I would also use BA's tool mentioned in the last paragraph of Gemac's post to look up availability before calling AA. To me, that is the fastest and easiest way, versus calling AA without any prior legwork done by yourself.