Austrian has the best catering transatlantic. Much better ex-Vienna than the other way round though.
Their coffee menu is a very nice touch. However, that isn't worth a lot on the overnight flight.
They used to have a chef onboard and an appetizer buffet card. I don't think that is around anymore since Covid.

The seat is decent. I prefer the 767 over the 777.
Reason is that every window seat is an individual seat.
If you are on the 777 there is an option they call the "throne". Every second row at the window.
Some like it some don't. It is extremely narrow at the shoulders in lie flat since the armrests don't go down. Also the footwell is much narrower since it is jammed in between two seats.
But I believe Montreal Vienna is a 767 anyway